Acoustics 101 Pro : Advanced enclosure design | Tanasescu Marius | Skillshare

Acoustics 101 Pro : Advanced enclosure design

Tanasescu Marius

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40 Lessons (6h 39m)
    • 1. 0 - Promo

      2:20
    • 2. 1.1 Contents

      4:05
    • 3. 1.2 WinISD Introduction

      8:28
    • 4. 2.1 Sealed WinISD design

      7:34
    • 5. 2.2 Sealed Excel spreadsheet

      5:33
    • 6. 2.3 Sealed SketchUp

      32:43
    • 7. 2.4 Sealed enclosure build

      14:19
    • 8. 2.5 Sealed empty box vs filled with dampening material

      9:11
    • 9. 3.1 Bass reflex linear WinISD design

      15:14
    • 10. 3.2 Bass reflex linear Excel spreadsheet

      9:08
    • 11. 3.3 Bass reflex linear SketchUp

      14:10
    • 12. 3.4 Bass reflex linear enclosure build

      19:58
    • 13. 3.5 Extra - Bass reflex enclosure with labyrinth style port

      4:39
    • 14. 3.6 Bass reflex linear results

      2:04
    • 15. 4.1 Bass reflex high output WinISD design

      9:08
    • 16. 4.2 Bass reflex high output Excel spreadsheet

      2:38
    • 17. 4.3 Bass reflex high output SketchUp

      11:27
    • 18. 4.4 Bass reflex high output build

      24:23
    • 19. 4.5 Bass reflex high output port tuning

      15:56
    • 20. 5.1 Passive radiator Introduction

      11:32
    • 21. 5.2 Passive radiator WinISD

      9:34
    • 22. 5.3 Passive radiator Excel spreadsheet

      5:44
    • 23. 5.4 Passive radiator SketchUp

      10:23
    • 24. 5.5 Passive radiator build

      8:15
    • 25. 5.6 Passive radiator results

      4:19
    • 26. 5.7 Passive radiator retune

      12:57
    • 27. 6.1 4th order bandpass Introduction

      3:44
    • 28. 6.2 4th order bandpass alignments

      4:08
    • 29. 6.3 4th order bandpass WinISD design

      7:16
    • 30. 6.4 4th order bandpass Excel spreadsheet

      5:07
    • 31. 6.5 4th order bandpass SketchUp

      18:31
    • 32. 6.6 4th order bandpass build

      16:33
    • 33. 6.7 4th order bandpass results

      5:07
    • 34. 7.1 6th order bandpass Introduction

      2:45
    • 35. 7.2 6th order bandpass WinISD design

      8:08
    • 36. 7.3 6th order bandpass Excel spreadsheet

      6:01
    • 37. 7.4 6th order bandpass SketchUp

      6:20
    • 38. 7.5 6th order bandpass build

      9:50
    • 39. 7.6 6th order bandpass results

      4:20
    • 40. 8.1 Box comparison

      25:06

About This Class

Design and build sealed, ported, passive radiator, 4th order and 6th order bandpass enclosures

Finished Acoustics 101? Time to step it up a notch. While we are still going to revisit sealed and bass reflex enclosures, we are going to go deeper into the subject, and touch more advanced stuff. As a bonus, a high output ported enclosure is in the course as well. Besides these familiar enclosures, we going to see some new. Get ready to learn about passive radiator enclosures, 4th order and 6th order bandpass boxes. We are going to use WinISD (which is free) to model the boxes and we are going to use the attached excel spreadsheets to easily calculate panel dimensions. Besides this, SketchUp will be used to make 3D models of the enclosures. I'm going to show you how I actually build them, and finally, we are going to measure them and compare them head to head.

Transcripts

1. 0 - Promo: Hello, guys. And welcome to acoustics. Wanna one pro? So this is the course where we take the original acoustics. Want one, of course. And kick it up a notch. First of all, let's talk about the prerequisites. So do you need to take a quick sticks one on one first? The first course? Yes, you absolutely do. I'm not going to talk about the basic stuff here. Do you need to take acoustics to a one? Well, you will see some measurements. And if you are curious off how to make those measurements, then yes, you have to take a quick sticks to a one. Also, the third course is not mandatory, because here we are talking about enclosures and not crossovers. So to design our enclosures, we are going to use we know as the which is a more complicated software, but it's actually free. It has a lot of options, and we will see how to use them. Then we are going to use some excel spreadsheets, which I made to calculate the panel dimensions. So you don't have to do that by hand. We have a bunch of these excel spreadsheets for every type of an enclosure, then we're going to model them in, sketch up. So we are going to learn how to a three D model speaker boxes. Then I'm going to show you how I actually build them. And finally, we are going to talk about the results off each individual enclosure. And since I mentioned enclosures, let's talk about the enclosures we are going to build. So we are going to build a sealed box, a bass reflex box with linear response. Ah, high output based reflects enclosure, a passive radiator, Ah, four Ford or Band Pass in a six order bank pass. And finally, we are going to compare all of these enclosures side by side. We're going toe. Compare their Anne quick response there impedance response. And finally, I'm going to place them in my car and measure their sound pressure level. I imagine that this is going to be a fun course, so let's go ahead and start with the first lecture 2. 1.1 Contents: First of all, let's talk about the contents of this course. So since in acoustics wanna one, we talked about a lot of stuff, a lot of basic stuff. I'm going to get to the point in this acoustics 11 pro. So we are going to start with the winner is the introduction where I teach you the basics off this new software because it's more complicated. And then we are going toe talk about different enclosures. So we're going to start again with sealed. So we will have sealed and based perfect, of course, in this course as well, but in a more elaborate way. So we are going to start with sealed and we're going toe design it in we nice d. C. How we will do that. Then we will calculate the panel dimensions within Excel stretchered. So I have excels britches for different type of force enclosures where you just punching some numbers and it automatically calculates the panel dimensions. Then we are going a three D model, the enclosure in sketch up. Next, I'm going to show you how I actually build the enclosure so you might get some tips on how to build it. And in the end we will see the results. And, uh, bear in mind that this process repeats itself for all of the remaining enclosures. So designing we nice, the calculate would be excels appreciate pretty model building kosher and then the results . So this is the same for the next enclosures which will be based reflects we have to base perplexing closure. One is with the leaner response and the other one is high out with the enclosure. Hi, Out with base reflects enclosure. Next, we will talk about Bessie radiators four former band best and finally sixth order Van Best . So this will follow the same procedure we talked about in the sealed enclosure. And of course, we have some some different particularities for each enclosure. For example, in sealed enclosure I will I will talk about the differences between an enclosure which will be empty and one which will be filled with the dampening material. And we will measure them up and, uh, compared the results. For example, for base reflects on the high output, the closure. We will use a circular port and we will tune it at different frequencies. So we'll have to cut the port several times and see how we progress. And, of course, for the rest of the enclosure, the passive radiator, the fourth quarter and sixth order band pass. You will have some introductory information because thes are new enclosures. We have not talked about them in the first acoustics. One on one, of course. And what will be extra For the fourth order Band pass, you will have an Excel spreadsheet, which will calculate sun alignments just like in the bass reflex. There are no alignments for the sixth Order, and finally we will compare all of these enclosures because I am going to build them separately. And we have one single before for each enclosure, and we are going to measure the frequency response and it quickly measure the impedance. And finally, I'm going to place them in my car and measure their actual sound. Pressure lived, so basically, this is the whole course, and it's going to be long and fun, so let's begin 3. 1.2 WinISD Introduction: So since we already talked about the sealed and based reflects enclosures into the first acoustics. 11 course Now we're going to go directly into box modeling. But first we gotta we have to get familiar with the software we will use, which is we know as the So let's open up the browser and go to Google and search for win Eyes the So it's the first link linear team dot org's. And when you click that, you have to Donald the laters. The version which is the one from 2000 x 60. So I'm not gonna download and run that he will have to do it by ourself in install the software mine is already installed and we are going to open it right now. So this is, um um how we names the looks when you open it up. So basically, here is the chart, uh, where we will see the frequency response. And here we will have different projects, and also down here we will have We're sittings for the enclosure. But I'm not going to talk about that right now. We will Seymour when we will actually design the enclosures. So now we have to. I'm gonna show you how to start a new project. So when you start a new project, you are greeted with this window with a bunch of drivers with the with the parameters already already there. So you just have to load them up. But I strongly encourage you not to use any drivers. Even if you have on lets you have a deal, S and w 10 don't use these parameters because they might be incorrect. Or maybe the manufacturer has released a new driver with the same name but different specs . So always, always add your room. So we're going to use the Jilly Jail driver, and we are gonna add it manually. So go ahead and click at New, and that's right down jail audio brand. I don't know what they put you to do this, but I Right, uh, the same over here and model is 10 w six of the three, and I'm gonna add test because I already have this driver in the database, and I want this one to be separate from that one. So go ahead, including parameters. And now, depending on your driver, you go to your a manufacturer website. In my case, geolock dot com and you search your driver and let's look at the parameters. So here we have the parameters limits bird out these windows so we can see all of them at the same time. So what's important in this case I want to show you we need is the auto calculates parameters. So we know if you no que years and Q Emma's you can calculate the cute ears, so let's start getting the parameters. 13 point a 30.12 hurts. The reason frequency curious is 0.543 Q m s is 9.2 to 8. So know when I click this or rather somewhere else you can see the automatically calculates it it 0.513 which is correct. But sometimes you will get different value. So anonymous. In just a second, the V s watch out. This is in leader, So to turn to 3.25 liters and ah, the nexus ex Mex in millimeters 19 millimeters And you can see we have also calculated, uh, you know the reference efficiency and s peel. So if you are stubborn enoughto modify this number and you can see here it is your 0.11 and , uh, overwrite it with 0.11 But let's save the driver as it is right now with this one over written. So let's save the driver. Ah, save No. When you create a new project, we should find the new driver in the list. So this is it. You can see the driver that fails. Integrity check. This is the reason why it's a good idea, not toe overwrite the calculate parameters. So if you go to the driver database, let's load G. Loddo this from the Test one and let's do it This and now it's blue. It's calculated automatic. And now, Ah, let's check if we have some remaining parameters that we might input. Gary is V X max. Uh, these ones are calculated S de and our e. So you can see are these 6.4. But since this is a duel of waste oil, if we go to the trip of Star War here, we can see that D c resistance is measured with the voice quills in Siris. But actually we will We will wear them in parallel. So we have to divide this by four. So 6.452 divided but four. 1.613 wine 11.613 on Let's click and a place we can see that this ones are calculated automatically. And now let's check is D in square centimeters so have 0.0 318 square meters. You have tow Multiply this by 10,000. Took it to get the square centimetres. So 318 318 centimeters. Now we still have some parameters lift. But this should be way more than sufficient to model of the frequency response off an enclosure. So let's say this driver and overwrite the existing one. Now when you create a new project, uh, you let's find the prepper jail audio. You can see the driver that integrity checks, Okay, and now we can click next. Now it already asks us information about our enclosure, and I'm gonna stop this clip right here, and I'm going to see in the next one when we will actually design a sealed enclosure 4. 2.1 Sealed WinISD design: So, lister from the beginning again, let's fire up Weiner s d and create a new project. And it's such for our driver should be the one with test at the end. This one. And now here you will be asked a number of questions so it will be easier to choose the right enclosure for your So, uh, now we have to sleep the number of drivers you can select as many as you want. In our case, only one and we have normal and isil Barrick loading and we will select the normal evidently. But in a short version, we're not gonna talk about the severity loading in this course. But the short version is that them. When you couple to drivers like in the image shown over there like face to face, you can you can amount them with the magnet facing the cone as well. The idea is that the air between the two drivers acts like a coupler, and you are coupling the two drivers to Gettler together and you actually have only one driver but the with the V A s in half. So, um, you will have ah much smaller box the size the man will be much smaller, but you will need an additional driver. So let's elect normal and click next. Here. We'll have to select the type of box. So we have sealed different type of boxes, which we will see later on. But now we will select close because that's what we are building a sealed box. And you have this small calculator over here, which we talked about the acoustics 11 uh, where, depending on the parameters off the speakers, you can calculate the E B p, the officious embed with product. And if it's closer to 50 then, um, the box is suitable for both closed in base reflects. If the number is lower than 50 you might as well go for closed and higher. It's recommended that you go for a ported box, so let's select clothes because we're building a still boxing click next, and now we can choose your line. So if you remember the Excel, a spreadsheet from acoustics 11 the first course, um, you will remember that we could calculate the different alignments, and the 0.7 or seven is indeed the maximum flat response. The Butterworth response. You can choose the lower 10.50 point 577 I think this is the vessel alignment. Maximum flat delay. But if I remember correctly, 0.5 The best transient response. The link wits rightly alignment. Nevertheless, if you want a higher Q t C, you can you can go higher and step into the championship alignment where you have that specific peak right below right before the response starts to roll off. But we are going to go the conservative way. Select the maximum flat response and click next. Now let's let the name let's go for Shield Box Jail W six so we can give it the name and click create. Now, basically, everything is calculated because because we have selected what we need to select, let me full screen this. Here you can find the frequency response in the wisdom in the window. From the left, you can have different projects. So if if you have more than one, you will have more curves over here, and you can, uh, click them all for on depending off off how you want to compare them. In this case, we have only one. So there's no need to do that. So again. Here you can modify the parameters from before one or more drivers. Here we have the box how we will set up the box. So since this is a field box, the only parameter we can play with is the volume. That's how it goes is the easiest box you can make here, you can add some filters. We are not gonna worry about that. The type of signal again, not of our concern, the parameters, the air parameters over here again, not of our concern. And that's about it. Here we figured if we click advanced you we have Q l and cue Kuwait. Um, no, que is the losses from absorbing material? And here we have, ah, 100,000 which is basically no losses. The higher the number, the lower the losses. And in the first course, we played around with Cuba off seven. You can modify it over here, but Curiel off 10 means a bit lower losses. It's just this fine. If you want to modify, just go here and enter seven. If you paid attention to the numbers over here, you can see that they didn't change the resident Ramos East is still 40.6. So this number represents that residents, because of the box toe, force the numbers to change because they haven't updated. Even though I changed the Curiel from 10th 7 just lay them up with the numbers over here. So if you delete 48 type, work it again, you can see that the resonant frequency is now 41.13. If you do that and it still hasn't changed, just add some zeros. You can see it. It started to update once more at some zeros, and then the number will update. But let's live it to 10. And let's is you guess he is 0.7 or four. It's 32 liters actually there 0.76 So basically, this is how you design a sealed enclosure. If you want the Butterworth response, the Q T cells Europe on seven or seven. Then you have to make a 32 litter box with, and it will have the resonant frequency off 40.74 hearts. And basically this is it. It's a simple as it gets for sealed boxes 5. 2.2 Sealed Excel spreadsheet: Now that we know the volume off the enclosure, we can go ahead and calculate the dimensions of the panels. And I can show you how to do these calculations. Or I can attach this Excel spreadsheet like I'm sure you are familiar with this, uh, and we simply import some numbers and then the results are shown over here. So basically, you can see into the attach the image, how the enclosure will look like it's just a simple box sealed enclosure with across brace like you already know. When you see an orange sell, you have to input a value there. So the evident. What is evident is that you should already know the thickness off the panels. In my case, I use 18 millimeter thick MDF. We already calculated the net volume to be 32 senses them. This is the net volume we have toe add everything that will be inside the box and displaced displaces that volume. So should be the volume displaced by the speaker. That is, if you are placing the speaker with the magnet inside or any additional bracing most of the time you will get the speaker displacement volume quoted by the manufacturer. If not, you will have toe somehow eyeball it and give it a, um, give or take volume. So if you go to the jail website, you should find the parameters over here. In this case, it's at physical specifications. And you can see over here the driver displacement. We are interested in the volume in liters. So let's go back 2.1 liters and depending on how you make the brace, so you have to calculate the volume displaced by the brace. They should be easy enough. I already calculated to be 1.3 litres. So now we know that the gross volume should be 35.4 liters. Now, we can choose different shape for this box toe, achieve this volume and just enter some random numbers over here. But bear in mind that the speaker let's go back to the physical dimensions. You have to remember that the death off the box monks be hired than e so larger than this number. And, uh, the width and the height off the box should be greater than a which is this number over here. But since we are working with like 35 liters of volume. That should not be an issue. So you simply enter some numbers. 360. You have two input two of them, and you can calculate the 3rd 1 So if I do like this and click this button, it calculates, deserve the external dimensions. Bear in mind that, and after all of the numbers are in the input area, the results will show. So we have the front, the back. You can watch this image over here and see which panel is which, and the top to bottom and the optional cross brace, which is this. It's actually a panel with these dimensions, and you cut the inside and you are left with this frame, which you can use as Bob Race. So when you do this and you say it's for example, you do not like this number and say, Hey, the height is too big. Let's go for 350 Now that you have modified this number, if you multiply all these dimensions, it will not be 35 leaders, so you have to either calculate the width or the death, so it it matches this number. You either calculate and here and click the button or this one. So if I click here, it calculated the depth. So if you multiply all these dimensions, you get this value. So now if you click calculate anywhere it doesn't, it doesn't do anything because the numbers already match. So if I remember correctly, how he did it is 339 on this 116 and calculate this is this is the box which I made. So when you input all these values, you just have to, uh, right now these and cut on your panels and then we are ready to build our box. It's simple enough. It will be more complicated in the later when we are doing more advanced enclosures, but right now is pretty straightforward. 6. 2.3 Sealed SketchUp: numbering to show you how toe make a three D model of your newly created box so you can see how it looks like maybe sometimes when you actually see it in three D, you can see the proportions. Maybe you will see some floors in your design. It's nice because you can show off the dimensions in numbers and you can give it to someone else, for example, in they can make it by using this three D model of the box just to give you a disclaimer. I'm not an expert in Sketch up. I'm going to show you just some basic stuff how you can make speaker boxes because most of the time, if you are going to search for tutorials on sketch up, you will see people designing houses on stuff like that. But when you are designing a simple speaker box, you just need the few tools and you're ready to go. So to start, just goto w w dot sketch of that calm and simply create an accountant or log in with Google . I already done that, and after you have log in, you can go here and click my abs, and you have a sketch up for Whip, which is free. It has limited the options, but sufficient enough to do what we need to do. So let's launch the APP. Start motherly. I agree, and this is how it looks like when you begin the project. So before we do anything else, let's see here we want to set the our dimension. So I'm going to work in millimeters and with nothing after the decimal point in the snap interval. One millimeter. And of course, if you like the work in inches, you can go ahead and do that. But I made all the Excel spreadsheet in millimeters because they are really hard to do, especially the more complicated ones with the labyrinth, the board style. And it's really difficult for me to make in millimeters in in inches. So this way it's a good way when we do. The actual three D model is that we will check how the Excel spreadsheet is working because this is like a debugging. If you find if you find that the Excel spreadsheet calculator doesn't work correctly, please tell me what have you found so I can correct the spreadsheet, so now we can close this up. We select our units and Ah, first of all, you have to understand how this works. So we have three different access. You will see that them we will have to work with the with these axes because the screen is two D and we are trying toe move something in three D in that is pretty impossible. If you don't think in terms off these axes And since we can do all sorts of stuff, you have to understand that when you click something, you have to select the tool. So if you want to select something, you select the select oh, and then select it. If you want to move something, you don't click and drag. You have to select the move tool first, and then you have to move it. So you have to understand how this process goes. But first of all, we have to understand how to look about in this area. So we have this girl as a reference. Now I'm moving my scroll wheel in. This is the pretty straightforward when you zoom in and zoom out. But, uh, if I move, you see, when I click, I actually, this is the select. Also, if you want to select something, I selected the girl over here. Uh, it doesn't move the camera. So to move the camera, you have ah different options. So if you turn the scroll wheel up and down, you'll zoom in and zoom out like I told you, If you click, the scroll will. So if you don't have a mouse with a scroll, will I suggest you go get one? A clickable a scroll? We also you click and hold a scroll will. Now I'm clicking. I'm clicking and holding the scroll wheel. And if you move, you can see I'm changing the angle depending how I am moving. And also there is another way to move When you pan around, you hold shift holding shift now and again click the wheel and hold it and you will see these little hand. And now I am moving. I'm panning around. He will see that this is very helpful when we want toe change where the camera looks so now that we manage how to look around So if you change the camera toe on awkward angle you can click this play bottom and we can see, we have Ah, different perspectives like that. Okay, so, uh, let's start by drawing rectangular shape because when we are drawing a box, we wield draw rectangular of panels, which are rectangular, and let's go to Excel spreadsheet in Let's draw this the bottom panel. So the bottom panel is 304 times 395. And to do this week, like rectangle here we have different shapes we have. Ah, Like I said, I'm not gonna cover all the functions. But I'm gonna cover just the basics to build a box. And when we will build more complicated boxes, you will you will see more advanced stuff. But for now, let's keep it simple. And, ah, just the draw a rectangle and you can see the we have. Ah, the rectangle is marked in blue. This is important because it draws it according to the blue access. To draw a rectangle, you have to two ways. You either click and hold and drag the rectangle and lick off Click There we have a rectangle I'm gonna press controls the tooth under what I just did or you can click. I just fast click and then we can do like this and then another click to finish the right thing. Most of the thing we will use the second method because we want to use exact today mentions . So now I clicked. I can move the mouse. I'm not holding the click so I can move it whatever I want. But let me check the dimensions wants against. We have 304 times 395. And if I start typing on the num pad 304 you can see on the bottom right corner I'm writing the dimensions 304 comma 395 and press enter and we can see our a rectangle over here that zo me to it and pan, It doesn't matter which tool you have selected. So now I have the draw a rectangle tool. But if I use the scroll wheel told or pan the shift plus a scroll wheel it, it doesn't matter. I want to show that the thing with with with the blue color because we are drawing a relative to the blue access. So if I click again in a draw, if I press that the arrows right now I pressed up. If I pressed down, it draws it relative to the other rectangle. This is not an access. You can see it in pink. If I press left, it draws is according the green access and right toe the red access. And this is important because if you draw the like this and you needed to draw it like this , you have tow rotate it. So either you draw it correctly from the beginning or draw it in one another access and then rotated toe fit. You're correct, Texas. So, uh, let me delete this. So when you select, you have to understand that you can select anything so you can select this this line over here or this face this edge, or you can applicant tracking select everything. And I'm gonna press the delete key and nothing happens. The race. I don't know what nothing happened. Should be able to do this. You see, when I when I delete that age over there, the face disappear because face is marked by him a closed, the closed loop or something. For some reason, that keyboard doesn't respond. I don't know why a place control Z. Maybe because of this expert. Okay, now it works. Great. So when you have ah, this when you have droned this rectangle, imagine that this has no thickness. So when we are drawing the panel, we have to extruded So have this push pull as it push, pull and we select the face and we can see we can go up and down. But instead of this, we will use the keyboard again and type 18 because we know it's 18 millimeters thick and press enter. And now we have our first panel. The bottom panel. Great. So, um, I'm gonna show you the move toe. This is the movie. If you want to move a panel, I'm going to show you what happens if I try to move before I make this as a group, because each individual edge or face is considered as its own entity. And if I try to move this, that you first we have to select. So I selected this This face, it doesn't grab the whole panel. If I tried to move, it tries to move this only this face. As you can see, everything stays still and I'm moving the face if I tried. If I click this edge over here and try to move it, it will move only that edge. So we have to make this panel select everything and click make group. If you click may component, you can introduce the a certain name or something. Ah, region just gonna say make group. And now when you move it, we can see we are moving the whole power And you can see that a red line over there. It means I'm moving it according toe the the red access. If I go down, you see a black line. This means I'm moving according to none of the access. If I move like this with the green and if you cannot find the axes again, click on it starts to move and place Christie arrows. I want, uh, to the green line. It's blue. And, uh, if you want to move it strictly across the red access, you can hold shift. So let me show you over here. You see, if I move up it it's not moving along the red access. And if I hold shift, I cannot. However I move the mouse, it stays on that access that there is a nice tip. Okay, so let's draw another panel. Uh, let's say, uh, we draw the front panel. So the front panel is Ah, 360 times 395. So let's drawn on the rectangle. And now we have toe draw it along the green access because this is vertical. So we have 360 Carmo 395. These are the dimensions. Let's extrude this toe 18 millimeters and then we have our Pam Any free look around, we can see it's not in the correct position. That is not important. Uh, first we're going to make a group like this, and now we're going toe, move it to the back. And when I move it, I'm pressing control so impressing control and tried to move it. And when I do this, I make on exact copy off this and click. And now I have another copy. Have to do this to this panel as well because we need a top panel which is identical to that one. And, um, now I have to make a circle cut out for the subwoofer. So to do that We cannot do it when this panel is a natural group. So let me select this one and move it somewhere where I can manipulate it freely. Okay, Now we have to select it and explode. This. This is it. The panel is now right before we made the group. So when you make a group, you make it one panel when we exploded, it's in the initial state, so we have to make a circle cut out. So, um, to do that, we have to mark the center of the panel. And if you move along the ages, you can see marks the midpoint, draw a line all the way to the other side and again on this side. And this is the center off this panel. You have to use the's techniques toe, find certain points of interest. So if you go to the jail sub for here, we can see the mountain hole is 229. Let's run this tow, tow 130. So we have to make a circle. You will find it in the erect tingle area, and this is a circle and just flick in the centre, click. And now we can move the mouse however we want. But we want to input the dimensions by hand and you can see in the bottom right corner. It asks for the radius. So half of that. So 230 millimeters, The radius is Ah, 115. So right now, 115 and then we have our circle. Now we have to delete the rest of the lines. So let's zoom click and president elite for each one until we have Oops, I just deleted that face and way needed and select old these lines and leave on Lee the circle. Good. Now, to make, um, a cut out over here, we select the push pull tool. And instead of making this cylinder, we go on the other side and click own face wherever on the backside, off the path and click. And here we have the cut out for the offer, and now we'll select everything and, uh, we click make group. Okay. So, um, now, uh, we have to move it in place some. If you start sketch upper and and you don't know how to move stuff, you will try to do something like this. Take this and move it. And you see, you cannot place it correctly because this is a three D space and you are moving across a to the scream. So if you want to snap it in place, always select a corner or an endpoint. So if I take this for example, I just clicked. I'm not holding the click button. I'm just morning right now and place it on the end point on that group. It will snap in place. So I'm going to click. And if I zoom over here, you can see it's perfectly and neatly fit. And again, I'm going to do this with the this'll one as well. And you can see because I didn't select the panel. First, it moved this panel. So let's take it like this and move it like that and then we have hopes. Okay, so this panel is the other way around, and this is a nice time to show you how to use the move toe. So we're going to select this panel that's more over here. Uh, I meant the rotate tool. So this is the rotate tool, and we are going toe rotate this panel along this access and you have to click on the on this panel on the face of this panel. And then, um, show it on. We Texas, You want to rotate and then click again. And now we have toe Snap it over here. Good. We have wrote in despair if you want to wrote it a bright you said this and do it like this and then like this. Okay, controls you too. Go back to where I waas if you try to rotate and do and do something like you write on a weird stuff. Ah, this is a different because this is a panel. If you have irregular object, let's say a cylinder or something like that. If you move it awkwardly and not keep reference the access, you will have a hard time or put it back again. Probably impossible. But these are much easier to work with. So let's put the panel in place and move it again. So, like the corner. But now the we cannot see it properly and now snapped into place and again the penalties not what have we don't wrong. So the bottom is 304 times 395. 395. Correct. 104. No, Uh, on this one, 395 this should be a 360. So it seems like we have to rotate these panels as well. Let's rotate this like that. Now, let's move it. That's select the back panel and more this will. There we go. No, let's create the sides as well. So the side is 204 times 324. Okay. And let's select the appropriate axes. The right nexus. I forgot the size, uh, 304 before Good. Now let's selected this face and push Pull. Why this is happening. Okay. Seems like the excess pressure is bugging this application for some reason. 18 millimeters make group. Now we have to move it by holding control. So we created not a copy, and then we have to place it inside. Let's if I move this out of the way for just a bit and more of this like that, and then let's move the other pound as well like that. And then we're keeping the this front panel a bit of side so we can make a, um, the briefs. So the braces 300 then 59. 359. 324 This 359 324. Select this. Push. Pull 18. And now, before we make the group, we have to make a cut out just like this for the offer. But instead, we're going to do, uh, rectangular shape. So first we have to decide how how think we want our cross brace to be, So I'm going to use this pan, and from the mid point, I'm going to go down, Let's say two centimeters. So 20 millimeters and go. I'm decide. And this ended the same here. You can see it snaps on 20 millimeters, because it remember my previous move. Okay, like this from here to here from mid point. The whole ship, because having trouble staying on these taxes and write 20 millimeters press center like this from here. So here and from the mid point millimeters And and now let's delete all this extra lines and click this face and do the same as we did with the circle. Go on. The other side and click on face. And now we have this frame. Which is this? The cross brace. Select everything and make group Good. Now all we have to do is put it in place. Select one corner and place it over here. Looks good. No said, look, this panel click it on the corner again. I can zoom in is the most. However I want when I have this selected. I didn't I didn't like the right corner. You have to click this one to snap it onto this corner like that. Good. And now we have to make another copy off the bottom panel. It's click the bottom panel like that and select the move Tool, hold control. And here we have the top panel selected on the corner. There you have your box. Now, as I showed earlier, you can use this toe. Put, uh, markers on how the dimensions of the box looks like Like that. So now we three d modeled our sealed box. We will see on the more complicated boxes. Uh, if I have anymore tips for you 7. 2.4 Sealed enclosure build: So this is a recording of the sealed enclosure build. You can see I have the panels already cut. Those stickers actually contain the name of the panel and dimensions. Uh, the company which provided the NDF had the cutting surfaces as well, so I chose to order them already cut to size eso. Now I draw the lines to make the brace, and I'm getting a big drill over here. I think number 10 and I'm going to mark the four corner 4/4 of the brace so I can use the jeeps off to cut that rectangular shape from the center. So we are left with with a hollow piece so this bigger can fit through it in the inside theme way. Uh, one more pass. Things should be put that way to scrap. And I would have to make the baffles. We have to cut the speaker cut out. And I'm just the drawing the diagonals so I can find the center of that panel is I want to play the speaker right in the center, and I'm going to use the jesper jig. So I'm going to drill a number three hole in the center. You will see in just a May What I'm about to do The jesper jig touches to a router like this, and it has holes for each circle from divisions off 1 16 of an inch. So this is Ah, us adapter us in the U. S. Circle jib and it uses inches. So when I have to make a circle in the millimeters, I have to make the transformation. So just place that pink in the right according to the size of your circle. And now a zey make the first pass. I slightly go, um, a bit off the middle of the thickness of the India. So since the end of 19 I probably said that the rotor dipped to about nine or 10. So right now I'm not I'm not drilling into the table. So now I'm going to flip the panel and I'm going to do the same thing. And since I made the first circle slightly above the halfway off with it, now I'm going to make a a nice cut out. So I made the circle and put that away to scrap. Now I have older panels. We should begin a symbol. So now I'm trying to figure out which panels goes where and we should bring the wood glue. Actually, a place those panel instigator in the and I'm trying right now. I'm trying to market the position of the race because you will see how I in these situations. When you have that cross brace, you can easily step a stack all the panel instigator without using anything. And after all the panels are in place, you can type them, tighten them up with clamps. So right now I am marking the position of the off the brace because I have toe place would grew over there. So I know what the But today the exact position. So now I'm opening a fresh bottle of wood glue and I have all the panels in place. What am I going to do? Is go and I'm going to place Would blue on all the panels and then I'm going to puzzle them up together. This is possible on Lee when you have this cross brace because it holds the side panels together. Otherwise they will go inside the box. If you do not have this cross brace, I am placing these pieces of paper on the table because, most likely, when you clamp the panels together the wood, the wood glue will start losing out and when it dries, If the glue is between the box in the table, your box will stick on the tape because the people is what is, well, most like me. You are going toe, pull it away from the table, but it's a bit of hassle, so placing pieces of paper solved this issue so you can see I am placing wood glue on the top part so I can place the final panel. As you can see, everything is in place. It has a small bond on the fresh boo so you won't have any trouble with the panels thing like this. Now I'm trying to of place papers on holder on all the bottom part of the of the box. So since I don't have big enough clams, I mean I do. But I don't have a sufficient number of them. The smaller was Do not 50 sparks. I'm trying to use these strap clamps, which you can use. That one was stuck for some reason, so you can see with the only one you are tightening from all the position except from up and down. So I'm going to use a strap. Um, after I put it in position, you want toe be? Is Titus possible? And then you have to screw it in tow, tightening even more, And I'm going to place it on the bottom in another one on the top. So when you do this, when you have, when you have these night degree pieces in each corner, practically each panels each panel alliance into place because it's forced to do so. And since you have that cross brace, it automatically puts each panel in the correct position. Now, as you can see, I'm doing the final touches. And now I'm tightening up in the same for the one from the bottom. I haven't go. I haven't gone all the way yet. Now, since I have big plans available, I'm going to use the miserable. Why not? You see, I'm tryingto put them a bit more to the center where the cross braces. So I have a pressure over there as well. Uh, putting one on on the oh, on the other side. So I'm trying to bring a big climb. So I'm actually putting pressure from the top as well, because that is what I'm missing. Actually, I'm catching the people is willing toe, but it doesn't matter. Uh, you can see I cannot put a brace on the ah top left corner because the table doesn't permit , but three clams should do it from top to bottom. Now you have tow, since it's all the clams are tighten up. You have to wait for the next day until the glue dries off. Now it's, uh, the next day, and I'm taking the clamps off. Do this trip clamp and the final clamp. You can see the paper has stick the box right there where you see the paper there. The boxer would have bean fixed to the table on what I'm doing right now is just making some markers for the binding posts marking the spots in the I'm using the Dayton audio biting posts. And you simply need to use a number seven drill. Just drilled two holes and that should be it for a fixing the binding posts. Now, of course, the tips are optional. Just get a sander and sand. I'm actually not feeling that speaker up using just places where the booth movies. Okay. All right, we're done. Now we have to place the binding posts, take the knots off, and then stick him into the hole now taking the nuts. So the binding posts are nicely fit to the box. I think neither. Number 10 and wrench. Then bring your cables. I saw there, uh, that terminal to the wire and again place the other. Not so you can squeeze tightly these these cables we have. Ah, good connection. Do this by hand until you can't no more and then bring your wrench and tighten a briefing up. I'm bringing the speaker. I'm just placing it inside so I can mark the holes using a pencil toe draw where the holes are. Then I'm taking the speaker off. You been difficult because the heavy speaker and now I'm the chicken. My grill with the number three drill, and I'm drilling each hole back. Hold residual in from connect the speaker. So the binding posts and then just grew the speaker inside, searching for the correct bit, placing all the screws and screw each one. This should be the box is finished 8. 2.5 Sealed empty box vs filled with dampening material: - now , since this is acoustics, one of one pro, we will measure our box in. Compare the results with the modeling software. Which is we NYSE. The So the volume was 32 leaders, and in reality, it's the same 32 liters and let's see the results. So I have to charts over here. I have the frequency response chart. Uh, this is the frequency response sharp. I have another one with the dampening inside. So, as you expect from a shoebox, you have, ah, very linear frequency response, which extends with the A nice roll off until the end of the frequency spectrum around 20. Hertz and I have another plot over here again, I have the two charts stacked onto one another. The green one is with dampening material, but let's compare the blue one with the modeling software. It says there was an frequency, um coincides with the peak in the impedance response. So in our case, the 39.7 hurts, and if we go to wean eyes, the we can see that it's 40.7. So again it's it's within the margin of error. 11 hurt. But if you are, If you really want to play with the numbers, it means that the quill is higher. So let's go to 50. Then again, plea with these. As you can see, the risen frequency is going down, but it's still not there. Uh, let's put a large number 100 and, uh, you can see in in this case it says 39.7, so you can interpret that the box has basically no leakage. And if that would be the case than the modeling results, coincide with the measured results. But let's not let's play some dampening material and see how that effects the results. Ah, we learned in the first acoustics one on one, of course, that, um, if you please dampening material inside your box besides the all sorts of benefits. Uh, the main idea is, um, the speaker will play like it's in a larger box. Bennett is so we can see what are the actual results. So after we make the measurement, let's check the frequency response and eso The blue line is the one with the dampening with tears so you can see that the response is more flat. The flatness has improved SSM um, it's characteristic off a lower, too, because it mimics a larger box. So if we go to the impedance chart, we can see that the frequency response besides the effect that the impedance hump is now, ah, bit lower. It's not that the spike ish so to say, but the actual frequency has gone down by, like 2.7 hurts. So if we go to denies the if you want to replicate this result, although I don't see the point in doing that. If you go here, this is the box. The leakage the Q l stands for ah box linkage and Q A stands for absorbent material. So, uh, if you have absorbing material, you have to reduce this number down toe fraud. Um three. And you can see the I don't think this is pretty much accurate. I prefer to live it 100 and play with the Travolta. So I'm going to increase the volume off the box to see the perceive the volume. So, Tracee, I'm going to increase the volume until I reach the new frequency response of the box. So if they're going to 40 liters, you can see now it's a 37.9, and we need to reach 37. So let's head back 45. We're getting close. Let's see that this is the correct volume, so you can see the Q T C has gone down from 0.7 or 7 to 0.66 And the perceived volume, if we do it in percentage 46 divided by 32 we have roughly 44% volume increase. But you have to take into consideration that we use them a material which is pretty dance. It's a pretty dense and we feel it basically 100%. So there is no exact formula to know your volume game because there is different densities , and it's ah, it very much depends on how much material you place inside the box. So the only way to do it correctly is to is to have a measurement microphone and measure the exact game. Actually, in this case with the mother German microphone, you are only measuring the frequency response in Portland boxes. You can measure the risen freaked out of the box, but if you want to measure the resonant frequency off the box, you will have to measure the impedance, so, uh, microphone won't help you, but anyway, you will need them. The equipment which I talk about in acoustics tour one toe actually measure these changes. So the conclusion here is if you feel the box all the way up with dumping, you will get a consists of considerable game in enclosure volume. 9. 3.1 Bass reflex linear WinISD design: Let's begin with the base reflects project. So this one contains the box with the linear response. So I'm gonna leave the, um, the sealed project open because I want to show you how you can compare different kers. So let's begin by creating a new project again. We have to select our driver like this one driver in normal configuration, and now we are going to select Vented. This is the base reflects enclosure and, um again we can select the different lineman's just like in the first acoustics. 11 course we have q B three, the Butterworth alignment that is be before in championship and so on. So we're going for the maximally flat response. So the q B three alignment and click next. Let's give it a name Base reflects to be in here. Let's go and click create and you can see that now we can compare the two curves. This response is calculated according to our alignment, so if we go to the box section, we can see the volume in the tuning frequency is already calculated. We can start modifying these numbers, but, um, it's not now interest because we want the maximally flat response and indeed we can see it extends flat all the way down in tow. The very low region, like 21 hurts, but the box is considerably larger. So here you can see I can play around with the frequency response so it shows in the top right corner, the frequency and magnitude. If I want to play on the seal response, I just click this one and, uh, and check different responses. And, uh and also I can If I want to view only one curve, I can check which one I want to see. So what's different here? Here It should be the same. On the driver side. On the box side, we have the joining frequency. Now we can choose it because it's ah, vented enclosure. And if we click that fast, we have another option because we learn the the first course. First acoustics one on one. Of course that, um, the box losses are made of three things we have the leakage quell the way which is to the absorption off dampening material. And ah, we also have now the new parameter Q p, which is the port losses, and you can see the absorption in the port losses, we can see a very large number because it's considered that that they are negligible. And, uh, okay, let's go to events. Um, here we can choose the shape of the event and the number events so we can't round or rectangular. In our case, we're going to build a slot reported box. So we will have Rick Tingler sheep. We will see at the high output, basically based reflects enclosure. We will make it using a round shape. So let's say use the rectangular shape and only one port. And here we have two selected dimensions off the port. And before we do that, we have to check the dimensions of the driver. The size of the port. Visit there directly correlated with the size of the enclosure. So the height well, somewhat dictate them. The height of the port is well, So if we go to the speaker physical specifications, we can see that, uh, this a is 250 and we know that the thickness off the panels will be 18 millimeters. So if we go and help me 250 plus 18 plus 18 the the port needs to be, uh, actually, the height off the box, the external diamond. The external height of the box needs to be at least 286. And I'm gonna choose something a bit bigger than that, because this box has 60 65 liters. 65 liters? Yes. So it's a pretty big box, So I'm gonna go for a 360. This will be the external dimensions. So, uh, one side off this rectangular port will be 360 minus double the thickness of the panels so minus 18 minus 18. So the port will have 324. Let's go to events. And, uh, right down. This is in centimeters. So 32.4 centimeters. And of course, 10 centimeters is way too much. Usually, I tried to go toe three centimeters and go up from there. So if it's okay with three I'll live. It'd three. Because if you increase this number by too much, the port will have a considerable length. So let's go with three two centimeters and you can see that the length is calculated at the 79.7 centimeters and um, usually I don't mess up with this and correction the formula toe, calculate the length of the port. Um, has this end correction depending on the shape. But just leave it like that, you won't get the precise results anyway, so this will be a rough estimate. We will see that when we measure the actual results, we will have some differences sometimes is good. Some things is not. So you have to take this factor into consideration as well. So what's good about the dynasty is that besides the frequency response chart, we can check some other stuff as well. And the the important, uh, the important parameter in building, um, reported box is the port air velocity. So click re airport air velocity. And here we have a chart. Here is the speed off the air rushing out of the port, measured in meters per second. And here is the frequency. So naturally around the resonant frequency off the off the box, you will have mawr Air movement, as we can see in this search are. But, um, anyway, the graph is way down. This is because, um, all these charts are calculated using one what you can see the system. Input power is at one more. What if we go to the power rating of the sub before, uh, it has 600 watts. We're 500. What's in the, uh, in the safe zone? So to say so, when you are when you are building a base reflects box, you have to take into consideration this air velocity off the port because otherwise you will have a noisy port. So if you punch a bunch of the 500 number here, you can see the, uh the graph goes up because the speaker will move more violently, thinks power reading, and we can see that at its peak we have 37 meters per second, which is quite a lot. No, I hear you ask What? What number should you aim for now, depending on who you ask, you will get different answers. But, um, in my opinion, if you have both of them ends off the port flared, then you can go upto 10% off the speed of sound. So let's be the sound is 340 free. If we divide this by 10 you have 34 meters per second And also, um, I don't see the point if in measuring the air velocity of the port that the maximum power handle all the wool for I usually try to go lower like I don't know, 350 Let's say 350 watts. Because if you play that Max volume, it will probably make a lot of noise anyway, So the portnoy's is the least of your concerns. So what I tried to do is try to get it, uh, lower than 30. So, uh, if you if you're flair, if you use in this case, we're not using around port. But if you are using around port, you can flare the rectangular port as well. But if you're using the around port and you have both ends off, the port flared, um, you should be safe by not exceeding 30 meters per second in the port, their velocity. So I'm gonna leave it like that, because again, see, the event is quite long and we want to use on l shape port so we cannot go toe very if I increase the event size. So if I go to four here now, the vent is larger. We can see that the port that air velocity has gone down, which is a good thing. But now the length is over a meter long, so it's gonna be hard to fit inside the box. So you have to make them at these compromises. Make the main event larger in them. Issue less Portnoy's. But you have ah longer port, which you have to worry about and fit inside the box. So I'm going to leave it like, own three centimeters with and accept the this, uh, bigger port knows. I think it should. It should be okay, but Toby on the conservative side always try to aim for ah, lower port hair velocity. Now again, some, uh, extra options that we have with denies the we can check the cone excursion and we can see that, um, from 300 hertz in up the cone excursion is, um, in the safe limits. You can see the red line 19 millimeters when we entered in the parameters 19 millimeters x max and then it goes down at the resonant frequency off the box, like we learn and then below the resonant frequency of the box. Then the wolf for loses control and the excursion goes higher and higher. So you have to be aware that them below 200 hurt below 20 hertz, Um, the who for will exceed three the x max. And of course, this is at the signal we entered over here. So 300 in 50 watts. If I under 100 we can see we are safe on the whole spectrum off the frequency bandwidth. So you have to take this into consideration as well. Maybe used a subsonic filter or something like that if you want to feel safe. So this is how you design a bass reflex box. We have, ah, 65.7 liter box tuned in at 22.4 hurts and we have rectangular shaped port with these dimensions three centimeters by 32.4 and the length off approximately a 80 centimeters. And now let's see how we can calculate the panel dimensions using the excels purchase 10. 3.2 Bass reflex linear Excel spreadsheet: So let's start by calculating the panel dimensions using the Excel spreadsheet. So like we learned from before, we have to import values into the orange sells. And let's start with the things we know for sure. So we know that the thickness of the panel will be 18 millimeters. That is the MDF I chose and the net volume we calculated. Toby. 65.71 liters. The speaker displacement, UH, 2.1 leaders E M. 2.1 liters. And in this box, we will have no bracing. The only bracing will be the actual port. It's better toe place, some bracing materials, but it's a bit difficult in this box and for the purpose off this example, I will not use any bracing, but it's recommended that you do now. The port the height has Goto denies D 3300 and 24 because it's a millimeters 324. 30 millimeters in width and the length is 797 Okay, so we have a lot of numbers in place thistles. The port volume calculated automatically because we have to add it all up. So the overall volume off the boxes are 80 leaders, which is quite a lot now, uh, the only thing we have to do is to calculate the width and the depth, these arty external dimensions. And we have two choices. Either we enter the death and calculate the with or enter the within, calculate the depth. So in my case, I used about depth off 400. I want the box, Toby a bit wider. It will be more proportional. Otherwise the death is too much. It will look awkward. So if we click this bottom, it calculates the with, which is 714. And we get this message that the port clearance is okay. You have to understand that basically the port since is this is a L shape port is limited by the depth and with off the box. Because if I enter something like 1000 millimeters Oh, the poor please is still kill it. See 1200 millimeters. Now you can see that, um, this sport is too large for this box, so let's go back to 797. I always like to click the these buttons because if you see if I enter another dimension. The volume has changed, but these don't change in real time. So you have to click. They have to calculate either one. So you see, the width is now a bit larger, since the volume is a bit bigger. But let's revert to our previous state. Um, another function we have. We can use a double baffle. And this is important because when you place a double baffle, you can see in this picture over here that the actual thickness of the baffle, um, contributes to the overall length of the port. And if I use a double baffle now we get the next 18 millimeters that we have to shave off the end of the port because we have it in the front, since the baffle now is doubled. So let's use a double baffle, and you can see now, since we use a double. Careful at this numbers. This number pops up because these are the external dimensions. So the volume one remains the same, actually, is a bit less because we the port volume is less but otherwise only in the external dimensions. The double buffalo fix the size. So one particularity about this sport, which I want to show you. Let's look on this top view. So when you are building the port, let's say it's ah, single baffle like in this picture. Over here you have 18 millimeters which is the front baffle. And then, depending on the depth off the box, you can make the port longer and longer. So let's like in this example uh, the first panel. It has a maximum dimension off 334. So you have 18 and you can go longer and longer. And on let's say you have 18 18 plus 334. This is the maximum dimension until you need to add the second panel to make the port longer. But as you reach this exact dimension 300 52 million meters off port length. So you place the first panel off 334 millimeters. Ah, you are ah, force the Indo something that you might not like. So as you reach the sport length with this panel 352 this port automatically uh, becomes port off 400 millimeters. What is that? Because Aziz, you reach this point. If we try to zoom in. We can see that them Ah, the length of the port is now this 352 millimeters plus this little l, which is 30 millimeters the with the off off the port and the thickness off the panel 18 millimeters and we go all the way to 400. So if the if the port needs Toby between 352 and 400 millimeters, you have no choice but to have a 400 millimeter port in this situation. And this is taken into account into this excel spirit Cheap. So, for example, let's keep this example and make a single baffle. If the port length needs to be 350 you see the first pounds 332. If I goto 352 then the first panel is at its maximum. Uh, they mentioned, and if I increase this number, you think that you see that nothing happens. You still have one panel with the same dimension, because now the port is actually 400 millimeters long. And if I increase if nothing happens until I reached this number, Excuse me. So now If I go to a 401 you can see that the second round, um, jumps into place. So bear in mind when you actually designed this box because this is a factor. You have to think it's into consideration and it's up to you on how you do it. So let's go back to our previous state. 77 797 So about 97 32 Yep, this looks about right. So this is Ah, uh, these our our panel dimensions. And now let's jump into sketch up and let's build this box. 11. 3.3 Bass reflex linear SketchUp: Now let's start sketch up and this should go a bit faster because we have already gone through the basics. So let's check the correct dimensions like this. And, uh, let's start building. So let's start with the bottom panel. We have 364 times 71 more. 364 Come on. Actually, it's the other way around. 71 basis for that looks much better. Let's select this face and push, pull it between millimeters and select everything in. Make a group like that. And now we should make, uh, the front Beth. So let's select the correct Texas on the green Access and prison the arrow like a like a torture in the first example and their mental. Let's go and check the front panel. 711 times 360 71 times six for a Santa. Now let's push. Pull this 18 millimeters. Now I want to make a copy of this because this will be the back panel. So first I'm going to make group and then move this by holding control. It will be the back panel and this I'm going to explode this because I have to make some modification Because before it becomes, uh, the front pan. So, first of all, let's draw the port. I'm going to zoom in on this. So we have Let's take the crayon from the middle. I'm going to go 18 millimeters like this, Like this. And from here, I'm going to go 13 millimeters here. I'm gonna go older, way up top. And now from here, I'm going to go 18 millimeters same on the other side. And now I'm going to select every additional line and deleted just like this. Now all I have to do is pull point full, push boulders going the other side in click on face. Now that is the port. No, uh, what concerns them? Speaker placement. We will go on the midway, uh, off this line, but the let's check. So the diameter is 200 50. Let's go. Let's take a bigger number. Solid C. I don't 304. And it's why despite too 170 so from the midpoint go 170. And that should be, um, the center of the circle cut out. Now select the circle. And, uh, now we have the mounting diameter, mounting, mounting hole diameter. 229. So 230 if we divide this by two, we had 100 and 50. There's our circle cut out. It's delete this and push pull going the other side click on face. And this is our Beth. No, I'm going to make group. And since this is a double duffel, I'm going to make a copy of this. So holding control and move it now I'm going toe stack it. So take this corner because I mean and bunch them up. So this should be our front. Beth, we can make this a group again. So it's a single piece. Make group like Okay, we can move it in place if we want to. Just like that, I'm gonna take the back. Panelists will its mortgage into frame. There we go. Now let's make the sides. Ah, so the rectangle and select the correct Texas the Red Xs 364 124. No, it's extruded eating millimeters. Make group. Put it into place. Old control to make a copy. But this to places well And now we have to design the port So I'm going to move this panel away so we can see what we are doing. And let's make the first port panel 334 324 standing on the Red Xs before 304 cool. Have to make group. Have to select the whole thing like that. Make group, and we have to put it in place now. So let's move it and click. Oh, click Death Corner. Let's malt. Now let's zoom in just like that Looks about right. And now let's put the second port panel in place. Let's check the dimensions. Um 3793 to 4. Okay, this 3 to 4. Okay, it's about Bush. Pull, push, pull 18 millimeters and let's make a group and let's put this in place. So let's grab the other corner like this and place it neatly please. Like that. That looks correct. Now let's place this paneling places well like that. And now if you want to check the Port Ling to see that is correct or not, let's take the pencil. That's view it from the top and go from midpoint all the way here. Now go down 15 millimeters and go all the way to the end and no good. What is this camera doing? And now go from here to here. Good. Now let's delete all the extra lines and measure, Uh, and let's measure them. So if we have 18 plus 18 over here and you can use the ruler or this thing over here so you can do like this and see the dimensions like that or if you don't don't want anything on your work area, you can just select the ruler and click this and go to the other side. And we have 400 12. So we have 412 plus 349 plus the double there for 18. Let's see. So we have 797 and we could go and check here. We can see that three excels. Bridget works fine. Like I said, if you find something that does not work corrector, please let me know. The Portland is 797 and if we go back, let's delete Oh, this stuff now we have to do is place the bottom panel on top. So we created copy hold control and move it. Take it like that and put it on top. And there we have our box. And again, uh, you're gonna look at it and check the proportions. Maybe at the mansions. Like I told you like this from here to here. Maybe you want to take this panel off and, uh, tell someone the dimensions. So you might as well give him a picture with, like this. You can do whatever you want. So this is the finished box in in sketch up. 12. 3.4 Bass reflex linear enclosure build: Seoul is third. The base reflects build. I already have the pounds pretty good, like, you know. And now I'm just measuring where I want my speaker cut out to be so the center of the cut out. And since I have a double, therefore, I'm gonna stick them together. So I driller the hole in the same spot. So I have to drill that, um, three millimeter hole for the sort for the circle jig now fixing the panel in place. And what I'm trying to show here is that the depth off the router bit is just about, uh, exceeding halfway so above nine millimeters 10 millimeters, 11 millimeters. And here I showed the circle diameter nine inches and 2 16 Now, since the baby is in police, you just have to insert it into the hole we just made and the cut the search, right? So use protective glasses, reduction headphones because the rather can get really loud. I think that motors is like think about something like that. Anyway, a high number and it's really love is bitter particular years. So I'm doing the same for the actually. No. I'm making a bigger danger, making a double baffle. Some choose to make a larger whole. So the sub before somewhat this it's flush and into the baffle. Thank you mean everything up and taking that scrap circle away. Okay. And that should be done for the circles. Now, for this box, I'm going to use this cruise. So when I am feeding the panels, I'm going to drill some pilot holes and then fit the screws, so it's a bit different from the first enclosure. So right now I'm drawing where the port will be. So, uh, I have ah bit of guidance when I'm placing the panels. See, this is the second battle of the port, and I'm drawing on, uh, on the back in on the front of the panel because one is used the s guidance toe placing the panel. And the other one is where I, uh, drill the hole so I can see where I have to drill the hole. So I'm going to start with the bottom panel and in the front panel the baffle and add wood glue. Place them correctly. And now I'm using this panel as well because they have to sit at 90 degrees. You can drill a hole and start screwing up. Start screwing this group. But the panel's might not be aligned at 90 degrees and you will have problems with your finished box. So I'm placing this panel even though in another another panel as well, even though they are not glued and I'm not trying to bind them together right now, uh, they served the purpose to place the two panels at exactly 90 degrees. So I'm taking the big climb off so I can have clearance for the drill. And I'm making the pilot holes like that and taking this cruise, and I have, ah, a smaller drills. The drill them inside. Yeah, and now I'm taking the clamps off. It seems that I'm drawing where the port will be putting the glue in, placing the first panel off the off the port again. I'm using some clams before I start drilling in. You have to align it, line it correctly. Otherwise you're going to have a bad time. So I'm placing the plant from top to bottom is well, because I'm going to drill from the bottom. Is what? So double check everything and then start drilling, drilled a pile of hope. Screw and I'm gonna do it from the bottom as well. So Oh, so I made three holes. So three screws once to three. That's that. I'm cleaning up the excess glue because you you really don't want Texas glue inside the port because we're using the flush trim bit of the router to make the whole. And if you have excess glue there that raptors cut that bit copies everything. If you have, uh, grew over there, it sometimes won't be a perfect worked angle when you cut the whole four before. So I'm basing the second the board panel tried toe put it between the lines which we draw earlier, then fix them with clamps and drill the holes square with this cruise. No. Okay, now let's place the side, put some blue and place the site. You some clams again, the same procedure. - You drill another hole from the bottom in center under the same for the other side, and our place in the top panel now is we finished the box. It's way easier to place the panels in place, - so I'm drawing some lines because I want toe drill holes exactly into the port. Now, The last penalty bet panel. Probably the easiest one. Just drill a bunch of fools. - No , I'm going to drill a big hole over there because I want to cut the port. Okay, so I'm using the flush crim bit. And basically, it will copy the inside the rectangle and cut everything else. It was like dead. Now we have to meet the all the rubbish from the inside. Theo, you vacuum cleaner. Now I have to please. Second panel, because it's a double devil. Play the glue and remember where the first screws are. So we don't screw. So you don't drill pilot holes into the same spot or in my case, over here, just used some clamps by I'm using this one to align the panel properly. You can use cruise like in like it did earlier, but you have to take into consideration where the first crews are. So you don't drink the same spot for you can use cramps like this and wait until the next day. So, huh, I think the solution is more elegant because you hide all the screws from the front panel like that. So it seems like the next day. We have some bad lighting conditions. I think I forgot to turn on the lights. So now we have to cut the second, uh, the second panel. Good. Now we have make the port basic. Now I'm drilling the holes of the binding posts Really clean. Clean it up there is finished. Now let's send. You can use the flush tribute like this to cut the the big excess. This is much faster than using the sander. Have to work the center a bit more. So just like this. Just cut the exist blue. Maybe the panels are not the line correctly. And you can cut the exorcist lectures using the flush crim bit anything that is to every corner. It makes the world a much easier when you go to the same. Oh, now did the center we've been? This is from the edges. Oh, and then we have toe drill the holes for the speaker, so I'm marking them up with a pencil. Take the speaker off. He drilled holes. I'm drilling three millimeter holes. I have to use bigger screws than three millimeters. Four or five should be enough. So it's placed the binding posts and the wires. You don't see much, but I'm tighten the nuts. You know where them up plays the speaker inside and used screws, and we're almost done. And there you have The box is finished. 13. 3.5 Extra - Bass reflex enclosure with labyrinth style port: now, as a bonus, I introduced this Excels. Appreciate as well. Where, um, we can calculate the panels off base reflects enclosure. But, um, one with a really long base reflects port, and we have to make this elaborate style port. And, um, let's use the same numbers from the earlier enclosure, so we know the thicknesses. 18 millimeters. The net volume is 65 71 75.71 speaker displacement 2.1 and no bracing. And the port height is 324 if I remember correctly. Yes, and 30 millimeters with and the length is the length is 7797 and let's make the dip shorter . So, um, it makes more sense toe approach this style instead of the l shape. So if I make 300 you can see down below. We have the panel dimensions, and now the port is made off two panels. This is the first panel, and the shorter one is the second pan. Now, depending on how long this sport is, you will have a number of these panels the first panel in one single second panel. So you might have won two of these, And this one is over here in the back. Shorter than this one. You get the idea, you can have one first the port panel and one second, depending on how long it is. So here, in our case, we can see we have to, uh, four size port panels. So 12 and this one doesn't exist. And instead, it's a shorter one with these dimensions. So just to give you an example, if I go lower in length, let's go 600. You can see we have only two or four size panels. And again, it's the same story. Uh, that's why you don't see um, no second panel. Even if I go to see I have a ghost. 610. It's still on Lee to full size panels. That is because of the same reasons I said earlier. When you are reaching the full size, you actually extending the length of the port toe this little L over here, plus the thickness off this pan, and this happens at every curvature. So when you start the new panel, you get this, um, length in extinction, even if you want it or not. So, um basically you get The idea is the same if you want a double bear four or not. Um so if you go to 800 let's see if you go to double bear full, you can see the port is shorter and it works in the same way. So this is just the bonus. If you want to make this laboring style port, you can use this Ex Excel spreadsheet to easily calculate again. I adviser to use the sketch upto design your enclosure and check the length of the port. If you'll find the mismatch. Mismatch is please let me know. So maybe, um, the excels Pritchard is a bug because these are not easily calculated. And maybe I'm missed a few things and the calculation is wrong. But for what I have done, the excels appreciate the works just fine. But if you find some errors, please let me know 14. 3.6 Bass reflex linear results: So let's look at what the results have we got for the base reflects enclosure. So we aim for a box joining frequency off 22.5 hertz and let's check the MP EMS response. If we look at this this dip between these two picks, which corresponds militarism and frequency, we can see that it's a 22.9 hertz and it seems like we did a very good job. But if you want the precise, the very precise measurement you have toe, take a look at the acoustical measurement. So the near field measurement off the speaker. So let's which the room acu wizard. So here I have the near field measurement of the speaker and this is the some response. But the port I have the port also, but it's not shown here because he doesn't for us any information. When we are looking at the near field measurement off the speaker, we can deduce the reason frequency, which is more precise compared to the impedance measurement, and we can see that the resident frequency of the box is at 21.3 hurts. So compared to how we model it in, we nice D, which is 22.5. We are off by one hurt which is basically in the margin of error. And we can conclude that we made a very good box according to our predictions. And if I take this and look at the overall frequency response so we can see that the response is very linear, just like we hope for because we want to twin toe for to be three alignment which is the maximum flat response. It goes well into the lower octaves, which is great. So this is ah, fortunate example off how you can model un enclosure and denies the and when you build it, you come toe precisely the same result. 15. 4.1 Bass reflex high output WinISD design: the high output based reflects enclosure This type of enclosures don't really want to build unless you are going toe those SPL competitions. So this box will some really, really bad But really, really love so depends on what you want to do. So let's create a new project Onda select the horse Speaker the G Loddo King Click next one revel in normal configuration ported and uh basically we're going to go for a championship a lineman, but we are going to modify it has we have to make a big box and we will use all the available space we have. And since we are placing the box in the trunk of a car, uhm I'm going to measure the trunk and see how much space I have available. So just click next for now and let's rename this toe base reflects, Right? Oh, okay. No, let's Let's Let's First of all, since I already measured that, um, available space in my trunk, I estimate that the volume will be somewhat 135 liters. So you go, asshole. I as you can to get this peak because he wanted to be as loud as possible. Now, this is not desirable because the response brought breaks linearity. But you get really loud in this area. So now we have toe select a tuning frequency and I'm gonna open heart over here. This is a somewhat similar to ruma que wizard, but it's another software. I did this project long ago. You can find an article in all your judgment that come about how to find the reason infrequency of your car. So basically, the yellow line over here is ah so possible for in a sealed enclosure. Basically, it's something with a response a linear response against he. It's sort of linear up until way into the 500 hertz. So you measure your symbol for near field so you're getting a any quick response and then you measure the same symbol for in your car and you have the skin was killed. The response because there is here. You measure the driver up close in the car, you put the microphone summer in your car, which is away from your roof for again after just killed the responses. According toe the distance you have this yellow line which is the symbol for in an earthquake the response any quickly and this one in your car. And you can clearly see here that in this area we gain the most amount, um, off output because of the car because here is just a subwoofer. And here is the sub four plus the car response. So the idea is we want toe June the sub before so that the box has its peak around this area. So if I center this, we can see it's around 34 hurts. So anywhere between 31 in 37 somewhere around this area will be great. And now, if we hit back to win eyes D, when you look at this charts in use, for example, tuned this toe 30 hertz can see that the peak is roughly around 30 hertz. But actually, when you measure the frequency response of your role, for you will see that the peak is somewhat above them arisen frequency of the box. So if we want to aim for 34 herds, we want to tune it a bit lower. Maybe somewhere here, 30 hertz. Let's let's see, uh, in this case, we will use a circular shape and ah, the diameter will be 50 centimeters. So this is a six inch port and we can see the length off. The event is 32 centimeters. Now. When you buy the port, it comes out of the box with 40 centimeters off pipe length, plus the flares. So let's see, for example, if I tune disappeared lower, you can see that event goes roughly in that area. So what am I going to do is since this is a circular port and I can cut it however I want, I'm going to leave it at its full size. So I'm going to tune, tune it to somewhere around 20. It hurts and measure it, see how it measures and then adjust accordingly because we want that peak. We wanted the peak to be somewhere around 34 hearts so we can check the air velocity. Okay, Now I'm going to put 500 watts because we are actually going full blast. But this enclosure so we can see the air velocity is quite high bug. But again, this is allowed enclosure. We don't really care about the Portnoy's. Uh, it will be flared on both ends. But if you really care about this value tried to aim lower than 30. So I don't even want to be on the safe side. If you have flares on both ends, maybe if you're at 25 it should be okay. But again, you have to test it, then see how it goes. So let's hit back to the transfer function. So yeah, basically, we want to aim higher than this. So you can see the peak is now at plus 7.3 decibels if we try to tune it higher. So let's say 34 exactly where we want to be to be. You can see that the peak here is it 9.8 days a bill. So as we turn it higher and higher, we get a bigger and bigger peak, which is desirable for us. But like I said, that Julian frequency does not always coincide with the Peking the frequency response of that enclosure. So we are gonna leave it at 28 hurts. So I'm gonna put the full port as it comes from the box inside the enclosure. I'm going to measure it and see how it measures. And then you do adjustments from there. So basically, this is it? So let's compare to this one. You're going to see how badly that basically, this is a bad responses. You don't want something like this on Lee. If you, uh I need these high pressure levels, for some reason, you're going to competitions or something like that. But this was some really bad. Don't don't do such an enclosure on this, Uh, the reasons I mentioned earlier. So let's head to the Excel spreadsheet because we're finished designing this box. 16. 4.2 Bass reflex high output Excel spreadsheet: So here is the Excel calculator for the panel dimensions of a base reflects enclosure, which uses a circular port. So I'm sure you're familiar with this design. So let's entered 18 millimeter thick panels. We have the net volume over 135. Speaker displacement 2.1. Bracing. Well, it doesn't really matter for such an enclosure. We want to go as high as we want. Anyway, let's just say two liters. I haven't calculated precisely. It doesn't really matter. And the poor Dimitris, uh, 100 then 50 and ah, religiously. For now that the length is 400 millimeters and we want to go a double path. Okay, so, um, I measured the my trunk, so I know that the wit I don't not want to exceed, uh, Let's see, 770 And the height, Uh, you don't want the exact height because you have to slide the box inside the trunk, so you have to be you have to take I'm a tad lower number because the box might get stuck on the way in. It would fit if you could teleported inside, but you have to slide it in. So you have to take this into account. So I chose the 390. So let's calculate this. We have 599. So the poor clearance is good. Everything is good. Everything is good. Eso basically these are the panel dimensions. And, uh, we now have the optional cross breeze, like in the sealed enclosure. And we can see here, this is the cut out for the port. And, uh, yeah, basically, it's straightforward from now on. So let's head over toe sketch up and, uh, make this enclosure. 17. 4.3 Bass reflex high output SketchUp: Let's do the usual millimeters. No, that's begin with the bottom. Ah, so we have 560 free. 770 Okay, let's push pull millimeters Soon. Make. Now. Let's make the front panel 3 90 77 90 those. I'm gonna do this on 7 73 Do it the other way. And that's Bush. Bull is 80 millimeters and going to make group. Move this with control over here, this will be the back panel and I'm gonna zoom over here and explode this explode. Let's mark the center and draw a line with the other end. And since the speaker has 230 millimeter diameter, I'm going to go something like 50. Let's hear 100 and 80 And here is the center. So right over here, Speaker has 230 millimeters diameter the cut out. I mean, we're going to go 115 radius. This is the speaker. And now the port has 216 diameter. So let's go 100. And so 108 has got 150 millimeters away from the edge, so that would be the center of the port and since, in its 216 we have to go Raiders off 100 that is the part. So now we're going to delete these lines. Looks on, push on face. Same with this on the face. No, we are going to make this a group and we are moving by holding control to make copy. Since this is the double therefore and I'm gonna place it right in front of us. Looks good. And of course, we are going to make this group one more time to be single piece. So let's move this good. Now select this and put it on the back, just like Great Britain. And now let's, uh, create the sides sites 563 354 It is a hard number to remember. 563 What? 563 Rick Dingle rectangle. Like this. 563 Ah, 354 Okay, let's push for 18 millimeters. Make group. It's more this place. Good. Make a copy by holding control, and now we have to make the cross breeze. So let's press the arrows already. Access. That's good. 734 354 And let's Oops, it's pretty cool. So everything. I'm doing something in the sex sells. Appreciate seeing that it works. I don't know what happens exactly. And now Ah, let's zoom, Ian. And let's say the cross brace will be Let's say, let's go to the middle 40 millimeters thick Because this is a big brace like this. Like this 40. There's 40 like this. 40. Good. Now let's delete the extra lines. Perfect. Click this face and push poor go to the other side and on face. There we have it selected. Make group. Move it, Click this corner. I think I'm gonna click this corner so this place should be correct somewhere along the middle. And, uh, let me move. This position doesn't look good. No, it does. So there we have. All we have to do is click the bottom panel and create a copy. Now, when you click it, you can press shift also to maintain He checks his chases, not the room green, huh? I want the blue, the blue so whole shift and simply go up When I holding shift, I'm keeping it on the blue access. So now it's perfectly parallel with the bottom. And of course, you can place it on a thought if you want. That doesn't look right. Click the corner zooming if you have to. Uh huh. This panel is not placed correctly. You can see the edge over here. So if I select this clips now, it looks good. Let's check the other side as well. This one looks good. So if I click this and click this corner, it slides into place correctly. And there we have it. This is our Heil. Put the base flexing closure. 18. 4.4 Bass reflex high output build: the build for the based reflects the high off both enclosure. So I started out by marking the center of the board. You draw the two diagonals and I draw a line through the center. Um, so I know where to drill the hole. 4% of the speaker and for the port. So I take the other panel is well, because we have a double before and I stick them together. So when I drilled the whole life, I drew on both the panels. So I think the three minutes a drill and drill the hole Same for the Port ST for the speaker. But some now I have to make the circle cutouts. So I dig my router and said the dip, but that being into the correct spot, that is the whole for the port Now, some problem occurred to the rotering. It was an old rather. So I decided to buy a new one. You can see I have a different for out there now. You don't want to mess with the these machines because you can get injured. So I didn't want to risk anything, so I bought a new shelter. And this one has a nice attachment where I can vacuum hold the dust that was not competitive with my vacuum. So here's the first circle finished. We have four circles because speaker in the court Double devil So four circles now I just read the report, and it seems like it's a little bit loose, so it would have been better if the whole was smaller. So when you're making such holes, it's always nice. It's always nice boob have, ah scrap panel and make a hole of this whole. And Steve, if the hole is large or small, and then when you make the actual on your actual careful, it's just about perfect. So, actually, now I know that the whole must be a bit bigger, actually, in the smaller I mean, on the second panel, off the double baffled, I'm going to make it smaller can. In fact, after I finished that whole, even though I made it smaller, I should have made it smaller spills when I am just again the port. I don't know why it was such a difference. Maybe I didn't calibrate I didn't celebrate well enough. Just circled jiggle in the new router, you know, so now I'm finishing the third hole. One more to go. Making my first fast. No, they sold. So now that I finished with the baffles putting my doctor back on duh you to make the cross brace. As you see, I'm checking the second hole because I made it the bit smaller now. But the battle away and I'm taking the panel, which makes the cross breeze. So I'm drunk. Some lines. I'm gonna make it like a frame. So again, just like in the first enclosure, the seals quarter. I drill it a 10 millimeter hole in each corner so I can easily use the juice. But that will get back and get the jigsaw. The jigsaw is working, actually exacting afterwards. But you're feeling here a lot of us. So it's best to use one of those masks. I don't have one, but I should one of those masks with death filters. So now I'm aligning the panels in place, just like in a sealed enclosure, putting some paper on the table so the box doesn't stick to the table. And you can see I already made some marks where the cross brace will be. I just have to apply the group. I'm switching my gloves so I have some junkie junkie gloves because you're going to ruin them. When when you use what blue, so apply the glue in the correct place is, you know, back panel the last one, and now tried to puzzle them together like that. Like that they hold in place because the blue, even though it's fresh, it still holds them together. So since this is a big box, I to come deliberately to place some more blue in the corners, so I make sure the boxes tight airtight. Can I spread it across? Take advantage of my junkie clubs. I use my finger directly. So now apply on the top part to play the top panel on the on the front and back, pal. Put the glue on the edge right on the age so it drips down because the panel step seen like that. So it has to make contact with the group. Now I'm taking my strep clamps and I want to place one on the bottom and one on the top. And again, this is a bit difficult when you are doing this by Rhone. If you have another pair of hands. It will be much easier. So I'm having a hard time right now placing the's clams in the corners. So one is done. I have to place the other one is well, and especially for these big boxes, Even for placing the panels together, it's good to have another force in to help you out and you'll see in a moment I run into a bit of an issue. And I think if I had someone help me, I wouldn't have come to this situation. So no, I'm tryingto tell him the clans and I see a problem. I am. The panels do not line up correctly. So I think this big clamp and tried to push the panels in the correct place. And even though I didn't the clamp, the panels do not want to fitted the correct place. Try to look inside and see. There is if there is any problem, it seems like there is not, and I take this trap. I take this trip down in a minute. We'll see at least the top one, I said, Get done. I could use the clamping force, apply a lot of force sea to land the panels, but instead the plan slides out of place like that. It seems like I took way too much time toe put the clamps and start I placed extra grew in the corners and such and such. And it took a long time till I actually put the strap lamps in place. Uh, now you're seeing in fast for, but I actually I was in a hurry. I didn't think this was a problem, but it seems like the Grew has hardened to such a state that I couldn't move the panel. It has its a large panel in a lot of surface area where the blue was holding on and I couldn't I couldn't move. So now there is nothing left to do. But, um, I'm gonna put the strap into place and put another clamp where the side, the cross brace is and use a lot. My village available clams. At least the one that that reaches. Because this is a big box. So the smaller ones I can clues, son, I'm just taking some panels and shaving off excess glue. So it depends not stick to the box. And I tried to place something, Harry and I'm using The previous box is placed on top. So I have live pressure. And the top panel sits nicely until the group completely drives off. So we will see the next day when the glue dries off that the panels are not perfectly aligned. But that doesn't mean that the boxes not airtight because it actually is. But it doesn't look good. This is the first time that this happens for me. So it's good to know. Hey, is that the panels has have a stick to the parks, so I have forced them out. Okay, but first time removing the crab clams I remember correctly, I punched them out of place. Yeah. Yeah. Now take the paper on. I'm looking at those cores because they do not look that good chicken being inside to see if there are any problems. And it seems that they are not. No, I have to face them. The second panel of the baffled. And then we will see what we can do with those uneven ages. So apply the glue and put the top panel in place. Put some clams. Okay? And now wait for the next day. So here's the next day putting my gloves on, removing all the clamps, and now I'm going to use the rather with flushed trimmed it. And I tried toe straighten things as much as I can, and then I'm going to use the sander. So why use Booth? - Of course. Some panels cannot be fixed with this technique. Uh, the sander Will we have much more freedom with this tour, so basically purposes. But oh, now. Okay. Oh, putting on the floor. Right. So I see a panel working router again. So that's what I'm going to do. Take the road out and trim their age. It's much easier this way when you can use the rotator, use it because much. So that should be enough with the sanding. Now I'm testing the port and that this port the one that the 66 inch port from of precision port, I think, um, it doesn't come with holes, so you have to drill your own holes. It does have, uh, a little marks where you have to drill the holes. It tells you if you want eight holes or six holes, I think it has a special marks. Were you need to drill the hole. So I think I drilled the hate holes. I don't know the larger number. Me good. So the holes I drilled were actually too small. So I took a bigger drill and drilled the holes again. I'm going to place it inside the box, and I'm gonna mark the holes with a pencil so I can drill them into the him Deif. You see, the holes are really close to the hole because the whole should have been small, but we are going to use some silk. Um, I use silicone nevertheless, because it it makes the connection between the port in the box really good. I find that the place the poor to directly on the box, even if it is a tight fit, even if the hole is precisely cut. So the port fits tightly into the hole. Uh, many times it will rattle around because it's plastic. Oneto would, and there is no damping between them and a lot of vibration. And many times, the port will read a little red. Elin's some really bad. So I use this technique not the most elegant. I'm sure there are more elegant solutions out there, but I use a lot of silicon and prison down until it starts to lose out. Then I use the screws to push the port into the box. You have to realize that now the silicone, just the silicone alone. When it will dry out, it will hold the port in place even if I remove the screws. But for now, we are, um, bunch of screws to fix the port in place could and have ah type bomb. So be careful when you screw the screws, because if you try to force it, this is plastic and plastic bricks. So you can break your port if you force too much. So don't try toe over. Screw the screw ups. So this is the next day after the silicon has cured and I'm using a sharper blade to cut the excess. So just mark a circle around the port. Just that this and then the exit should peel right off. Now get some sanding paper. Onda uh, use the knife a bit more if you have to shows, do what you can to make your life a bit easier. So there we go, a bit of excess removed, you know, take your sanding paper and easily, but surely make it look pretty so you can see it doesn't look that bad. But I can assure this this sounds way better than just placing the better port. So this is 19. 4.5 Bass reflex high output port tuning: no. Okay, so, no, I'm going to cut the port. So I measured about five centimeters. So I'm removing five centimeters from the overall length of the fourth when you're doing his best, that you cut in small increments. Because if you cut too much and you want a longer port, you have to give the new pipe thin pieces to get a middle saw to cut. I think this is a difficult pipe is very large. Six large and hurt. The four inch pipe is easier to cut. And I'm looking If I made a straight cut, it seems like didn't so that is what I mean. So, um, I'm trying to fix this problem in, uh, trying to find some sanding paper with a rough grit so I can easily remove the excess and flattened end of the pipe. You say I'm not making much progress with this technique, and so, uh, this means you have to make sure when you actually cut the pipe that you do it correctly in the straight way. So take your time. Don't be in a hurry right now. Using the orbit, people make my life here. - So I removed the A big chunk of that part, which I wanted removed, but I'm still trying to smoke. I think is a good thing. I think I found a place descending paper on the ground and wiggle. Wiggle the 500 us and favor. And this will make a nice straight space show. Ends of pipe. Just take the time. Depending on how state you have cut the pipe. This will take more or less thing when they are in checking the connection with the flare. Uh, so this six inch flare, Um, there's something weird when you connect the flare. So on one end, you can connect it easily, but on the other, and it doesn't want to. So I found I need to keep up with Claire. So gold bigger in size, Good plastic on. I'm placing inside the box. I know covering up the holes with some Indian panels. And I'm pleasing this panel on the cold floor because you want that to shrink in the other one toe, grow in size so they fit is a Normally this doesn't happen to what the ports. I have used it to the sport each port because anybody 61 so no you can see. I can feel it inside. Uh, and now I have to pay to attach the other end of the port. So the second having a heart, thank you getting. And this one is the one that connects normally, so I don't have to heat it up. So here's the port. So now that the first iteration of cutting off the port is finished, let's check the results. So before we see the results for this sport, I actually measured the full side sports. So with the 400 millimeter pipe, plus the two flares. So I have the speaker, the port and the combined response. But I'm only going to show the speaker and the combined response because the speaker shows the resonant frequency off the box and the combined response. Show us the peak off the overall response because we are aiming to have that big at 34 hurts. So this is, um, the port in full size, and you can see that the resonant frequency is at 23 point free and the peak is at 25.6. So exactly what I told you, the resonant frequency off the box does not coincide with the actual peak in the response in the frequency response off the hold Assemble. So let's check our first iteration. So after we cut that piece from it, this is the speaker. So the resonant frequency has gone up to 26.18. And if we look at the peak since the resonant frequency has gone up and the volume stayed the same, we can expect an increase in efficiency. And the peak is around 27 hurts. So of course we're not at the 34 hurts, Mark. So I decided to cut another piece. Now let's try and cut another piece of the court's time booth something. Okay, so I'm measuring. Seems like seven centimeters and I'm making marks all the way around the pipe. And now you can see I take my time. Also, it will be easier to smooth the edges of the cut that exist. So I'm making a small group pull over the pipe. So when I make the cut, the soul will not, uh, move around in the cut people Somewhat straight. I found that this middle, so is the best for cutting pipes. Do not try to use a table saw because plastic is brittle and it'll probably breaking to pieces. You can use Dremel so those small routers shows can tell. And, uh But I think this one is more precise with this Hansel. So with some plans to help you do your best as treat this possible. Then again, I'm using some sanding paper to smooth out the edge. Now, my cut was indeed the way more straight, but I still saw like a king in My cats are trying to remove it, and the only way to remove it is toe Keep on sanding. Your defect disappears. So depending on how patient you are in how perfectionist Who are you going to do this? Smooth. So I guess, uh, it's fine with that little defect over there. Now I have to heat up the flair once again. Okay, so go ahead and take the hair dryer. Important box detective gets quite hard and actually ruined the hair dryer. He died on me, but I managed to complete the report inside. So don't use a hair dryer for this procedure. You can see I from the next on the next generation off the port. I used to keep guns, so he was a heat gun. It's a more professional if you want to do it this way with the hairdryer, you are risking breaking your hair dryer. Now I'm placing the speaker inside, and after we are done, we shall see the new results. So now that we finished cutting an additional piece, let's check the response. So I'm going to untech this too de clutter the graph chart. And let's, uh, we have the second cut. Here is the speaker, so the resonant frequency has gone up like two herds, and here is the combined response, So the peak didn't increase much in magnitude, but we can see that the peak is now at 29 hertz. So we're getting there. No, this is the time. I realized that before I cut even more from pipe. I should try placing just the flares to get so remove the pipe, hold together and stack the two players better, and basically you have the smallest, the smallest possible port. Just the two players connected, so now I'm using the gun as I should from the beginning to flare up, and I'm placing the other one said Box and connected directly to, so that should be just placed the speaker back inside. And let's do another test. Okay? Now, as you So I decided, toe stop cutting additional pieces and just placed the two flares to get her and see where the response leads. So we can expect Ah, higher tuning frequency. So let's check the speaker and we can see that you need frequency. Is that 37 hurts? So this is not in our plans. So let's see the overall response like we expected on increasing magnitude. But the peak is at 38 hurts and we are aiming at 34. So, um, the solution used to cut a small piece and put it between the flares and hope we get the result that we want. Now, this is the final tuning. I'm just leasing a smooth piece of five from the earlier cutouts. So the piece which remain after cutting not the one that I part inside, boss the other part because it is quite a bit small and we should see how this will work for us. So fixing the pork and placing the speaker, and soon enough we will see the results so now that we have placed the additional piece, let's see the tuning frequency, which is that 31 hurts. And then the overall response we have the peak head around 33 hurts. And basically we are going to, uh, except this We're not going to aim for 34 hurts because that is way too O C D. So 33 hertz is just as good. 20. 5.1 Passive radiator Introduction: let's given introduction about the passive radiator enclosure. So this is how it looks like you have a new active speaker and a passive speaker and that passive speaker. It's actually like the active speaker. But it misses the motor so it doesn't have the magnet, the coil so older parts which are associated with the motor eso. It's called a passive speaker and sometimes is. It's also called Drone Co. So basically this enclosure is very similar with the base triplex enclosure. But instead of that pipe you have you used as support, you have the the passage radiator, which somewhat does the same thing. So we will see some advantages and disadvantages. We are comparing the passive radiator with the base reflects enclosure because it's, ah, good comparison. So let's see the advantages over based reflects. You have no more event and non linear parities, so when you have a very long pipe, you will have some distortion introduced by this. Because the piper will start to resonate, you will have no air turbulence noise, because when you have a ported enclosure, if the port is not the correct size, so it's smaller than should be, then you will have shuffling. So when the air rapidly escapes the pipe, um, it produces unwanted noise. Next, no more high frequencies reflected out the port. So in theory, the the massive air inside the pork should block any high frequencies because they have such a short weighing wavelength, they cannot pass through this massive there. But of course, in reality, things are not perfect. And sometimes they do escape through the port. So you have none of this in Ah, Pasig radiator designed because you have that cone which blocks thes frequencies. Uh, this enclosure is space efficient. And this is, in my opinion, the best reason you should choose a passive radiate earnest and the base replacing closure . Because sometimes if you if you're designing a base triplex enclosure in, uh according to the parameters of your speaker, let's say you want to build a Q B three alignment box in, um, it doesn't demand a big volume. So to achieve that Q B three alignment, you need a box with the low volume, but you have to tune it low. That means that the event will be really, really long, so you can imagine that the since you have a very small box. There is nowhere to place that port, and when you are facing these situations, some choose toe. Place the port outside of the box, but that looks very awkward, and it makes the overall volume occupied by the box import very large. So your best bet is to choose a passive radiator is that and you see this concept in portable speakers nowadays, if you take a portable speaker box, odds are excellent that it's a passive radiator design because it's such a small box. And to get the extra boost in output, you want to make it a base reflects. But since it's so small, you cannot make you cannot fit that port inside and you choose a passive radiator. Now let's talk about the disadvantages. The passive raid either has a steeper Rohloff. Compared. Toa base reflects it has less transient stability. It has a slightly cut off frequency, so the the response starts to roll off sooner compared to base reflects, of course. Um, since you have to buy a second speaker, it's not as expensive as the active speaker, but none of the less. It will be considerably more expensive than a piece off pipe. And, um, the passive speaker has limited excursion. You can imagine that in a pipe. Ah, the excursion is not limited by anything. The air escapes more or less freely for the port. But you can reach the excursion Inimitable passive radiator in in some cases. And let's talk about these excursion in more detail. So, uh, what's important is that when you choose a passive reader and the passive speaker, it needs toe have a VD off a least twice as large as the active speaker. So when you check the parameters of the speaker, this this V D is actually the area off the speaker times the x mess. So the volume of air moved by the Speaker s the which is the area of the speaker times X max. And this is of course, a volume. So if you take our speakers, we can see that our passive radiator has a VD off 855 cubic centimeters. And if we go to our active speaker, the jail wolf for we do not have these parameters, but we can multiply a SD by X max. And since we have the units in millimeters and in square meters. We have to convert these into centimeters and then we multiplied them but each other and we get the result off 604.2 cubic centimeters. Now we can see that those numbers are not that good. So the passive speaker needs to have a VD off at least two times that number. So our falls in 208 cubic centimeters and the passive re leader has on Lee 855. So the solution is to use a passive speaker with the higher X max or larger diameter. For example, this is a 10 inch radiator. You can buy the same radiator, but in the 12 inch variant or, ah, simply add another passive speaker of the same time. So when you add another another speaker, you basically you basically have ah, double the PD. So 855 times to you got 1700 so way bigger than 1200 which we need. So bear in mind, because when I made the enclosure, I firstly use just one passive reader and hope that everything will be fine. Since these passive radiators are not cheap. I tried my luck, Which just one person radiator. And it worked fine at up until, um some random volume level. But when you exceeded that, you easily reach the limit excursion of the past breeder. And it sounded awful. So you will see when we were when we are going to build this passive radio enclosure, you will see that later I will modify the enclosure toe, have an additional driver, and I'm going toe. Say this again. I said it when I build enclosure when you are placing your radiators first, I placed it on the opposite side of the speaker since I wanted to use only one passive radiator. But if you want to place to make sure, you place them in opposite panels. So one on the right one on the left, because when they move, they cancel their right vibrations. Now, since I had a place, I have no other options because the holes were already made for the first passive, really either. So I placed the 2nd 1 on top. That is not a good solution because the vibrations add up and the enclosure will be unstable. So make sure if used too passive really years. You place them on opposite panels, the enclosure will be much, much, much more stable. Now let's look at the frequency response comparison. And here we have 3/4. You can see the sealed enclosure, which extends Ah, the linearity extends the least, but has a very shallow roll off slope, as we can expect. Form a sealed enclosure, the base reflects goes more onto the low end. And we have the passive radiator in between because, like we said, we have Ah, steeper Rohloff curve compared to the base reflects and you can see that little notch over there That actually marks the resonant frequency off the box. And it's because that notch the that matches the reason why it has a steeper roll off stop slope and less transient stability. But like I said, if you want more low end output and you want to keep your enclosure small, then I think this is a better solution compared to base flicks. Otherwise, I will choose based reflects her any time of the day 21. 5.2 Passive radiator WinISD: So let's designed the passive really their enclosure using we know as the so we have the thes projects, which we made earlier. And let's create a new one. Select the driver. Chill on your next. So one driver and now we select passive. Read it and quickness. Now we have to enter the parameters off the off the passive radiator. And here you have to pay extra attention to so the units because we see we have years over here. And if I open them the parameters spec sheet off our radiator, we can see the V s is in leaders, So 59.7 litres. This is, um, uh cubic Desam eaters. And if you want to transforming cubic meters, you have to divide by 1000. And this is the number you want to enter in green eyes. D So 0.0 597 0.597 Que a mess. This is a unit, Lis. Uh uh que his unit list. So we copy as it is four point nine to 4.92 Fs season hurts. 19.6, uh, 19.6 s D is in square meters So we have square centimetres here. So let's bring up the calculator. Let me close. Older 356.3 This is square centimeters. If I divide by 100 this is square decima teachers and once again, by 100 s we have square meters so we have to copy this number 0.0 3563 0.3563 Good. And the X max is in meters kind of awkward, but that's what it iss you have 24 uh millimeters. So 24 we divided by 1000 0.24 the 0.2 and click. Next we have no land the live available, so click next you and click create. So this is our curve for whatever number we have here. So we have a 50 liter box now, Um, one of the reasons you want to build a passive radiator box Eve's that you need to make a small box and you have no room to place. Base reflects port in that small box. Because as the smaller the box gets, the bigger deport has to be. So you imagine the problem created there So in that case, I want to really exaggerate things, and I want to go to make the box as small as I can. Probably not the best truth, but that is what I want to do. So I'm going to make the box 18 liters off a net vault. Like I showed you Play but the comma for dot put some zeros toe. Refresh this number. This is the reason efficacy of the box and this doesn't look quite bad. And it's interesting to see toe have such a small box. Uh, how it plays. So now we have this passive radiator section, and, um, here we can play with the number off passive radiators or add mess to the cold. So, um, um, this is the bear passive radiator. With the no one waits on it. You can add weights as we can see here in the specification sheet. Uh, this is the moving mass with zero disks, and we can have 1234 or five discs. And this is the moving mass goes up. And the resonant frequency, as we see on the, um the row below goes progressively damp. This is how you tune a passive radiator. So, um um, if you want to raise the resonant frequency of the box, you cannot do that. You cannot lower Attn. The moving mass off the driver. Instead, you can add to drivers or or more so if I had to Drivers with the same moving mess The resonant frequency has gone up. You see now is, um 54 hurts, and since the volume remained the same, we got this hump over here. So let's ah, choose this back toe one. And, um, I'm going to build this box with no wait and see how it measures. And also, I will them add, um, I will add the weights to the box, and, uh, I'll add the weights to the passive radiator full waits, a mean and see how it measures just to make a point on how this works. So if I go back over here, we see that with five discs we have on additional off 375 grams. So this is the bear Speaker, and here is with five discs. So the difference is 375 grams. And if I go back and add here, you can see that this is in kilograms. And if you take the calculator and devise despite 1000 you have 0.3 75 kilograms. This is 0.375 kilograms, and you can see that the boxes June very low in this case, that 24 hertz and the the their frequency response looks a big awkward, but this is just, for example, seek. So we will make the box and the measure the box with no weights and checker with the Win Eyes D how we model that the frequency response and again put all the disks in place and do another measurement and see how it measures again. So we have to write these numbers down the second time we have 24 hertz risen and frequency in the first time with zero added mess. We have 41 let's say 41. So we're going to build the box and check this how these her numbers stack up so compared the model frequency response with the actual measurement 22. 5.3 Passive radiator Excel spreadsheet: As for calculating the panel dimensions for the passive radiator enclosure, I'm actually going to use the sealed box calculator because actually it's quite the same thing. So if you look at the image over here, we got the speaker place on the front baffle and the passive re later on the back. So basically we're designing the sealed box. Well, I'm not going toe place the cross breeze, so we have no bracing but the radiator on the back. So ah, let's said the thickness, which is 18 millimeters. We calculated a net volume to be 18 liters. We know from earlier that the speaker displaces 2.1 leaders. We have no bracing, but I will adhere the voting displaced by the passage Brady. And if we go to the technical sheet off this passage free, either you will find that this number does not exist over here. So when you encounter this problem, you just simply and enter something that seems about right. So I'm going to say our No. 0.85 liters. This is the volume displaced by the past radiator. It's not actually the bracing, but it serves the same purpose. It adds to the girls volume off the box. So now, Ah, when I'm change. Choosing these dimensions since is such a small parks I have to take into consideration the overall dimensions, the physical dimensions of the speaker. So this number here A. It's 267. And if I add two times the thickness off one panel, we have 2067. Excuse me? 7 18 So at least this number just to be safe. So I'm going to use, um let's say three Home 300 yeah, and, uh, the height. Let's go a bit higher than this. I wanted to be a cube or something like that. So I always entered different numbers. But it will be something in close in this range. So let's say 325 and let's calculate this number. So the depth is 301. So this is the external dame action and the we need to check this number because we have the speaker. The back of the speaker faces the back of the passive re leader and we need to check that there is enough clearance. So let's go to this and we have which is 1 75 plus mm plus plus. Plus. Let's go to the best free leader. Los we see here 77 with this with the with the frame. So, actually is 77 minus minus this 9.5. So I'm going to say minus 10 have 77 plus 77. So we have 242. And if we go to the calculator over here, uh, we have to bear in mind that we also have the baffle, which which helps us. It's a double baffle. So, um, we have 300 the external dimension Uh huh. Depth wise, which includes a single baffle. But since we're going to go double back way, we go 18 plus 18. So actually, this is the number minus 200. Effort, tow 142. We have 94 millimeters off clearance between, uh, the back of the speaker in the back off the passive radio. And if we haven't gone the double baffle room, we still have, like, six centimeters of clearance, so it should be just fine. So these are the dimensions off the box. We have to exclude this optional cross brace because we are not going to use it 23. 5.4 Passive radiator SketchUp: And now that we have the penalty emissions, let's start this ketchup on and that's set up our dimensions. And let's move a bit over to the side and and and, uh, okay, let's start with bottom panel as usual. 265 3 10 265 Cain. Let's select this and push pull 18 millimeters That zone, man and has made this a group. No, let's go ahead and make this the front panel. Three time 3 to 53 10. Just the arrows. So this one, the green access to five common 3 10 Just like that. Select this face and let's push Pool 15 millimeters. Make work. Let's move this into place because I think it's upside down. Indeed, it ISS and Chili. How much is this? 265 265 Okay, this should be the depth. Let's rotate this form like that. Nope. There we go. Always. Great. The corner. I Okay, so this is the front baffle and let's make a copy of it. So let's hold control. Move it over here and this one. So we have to make different holes that this one will be. We have to mount the speaker, and this one will be the back panel. And we have to mount to the passive radiator. So, um, I'm going to mark the center off each Powell again. This song, Actually, we have to explode them first. Like that? Uh huh. Its mark the same. No, I think it's that name. Why? Something is wrong with this rectangle there. Did I leave this face? I think not. It's there, so we have to make the circle cut out for the speaker. First, let's let the circle and go from the center. And we know that the speaker is 230 millimeters. So 15 The radius. This is the speaker and let's de lead thes and push pull on the other side, click on face And in this one let's see the this 1 235 Let's say 236 230 61 Look, 280. So this is the radius and let's head back and make this circle 18. Delete extra climbs and push coleus all the way to the other side. And this is the panel for the pest free, So go ahead and make group on both of them. And now let's make a copy because we want to double the bathroom. Hold control hopes I haven't selected. So actually, I made this one since it was selected so sticking together. And now let's select the other one and do this. See old Control to make a copy and then correct. Zoom in if you find it difficult to place them in the correct position. And now let's, uh, make them a group again. A group wound. Make group and let's place them into position. So let's select this one and grab the inner corner and put them like that, seeing for this one. Good. And now let's make the sides 265 to 89 265 to 89 rectangle. Select the correct access C five comma 289 Make sure you push pull this 18 millimeters selected and make group and straight to place. It looks about right on. True to make a copy. Is it in place? It's Hillary the in place Nice. And to make the top part, just click the bottom panel move told control, this is it just like that. And this is our passive radiate hurting kosher. Okay, this is much better. It's simple enough. Small box looks good 24. 5.5 Passive radiator build: So this is the passive re either build. I placed the camera on top, so you get a different angle from where I'm building. Seems, um, we have to effective speakers with a double baffle. I need Teoh make for circle cutouts, and I'm going to skip for this because you know how I do it. So here I have the four panels already cut, and now I'm going to use, uh the same technique I used for the normal base reflects enclosure. So, uh, drilling pilot holes and using screws. But again, I used the panels. So you saw. I, um, placed glue between the bottom and the front panel, but I'm using the sides on Leah's guides. So those panel those panels are at 90 degree angles. No one in placing one side, the right side again use clamps to help put it into position, even from top to bottom. Because I'm going to place this cruise there as well like that. Now, it's thanks for the other panel. I open a fresh bottle of glue if you hear annoying sound on the background. That is because this place is near a factory which makes bricks and that is the sound off the press. Uh, and since I have the windows open is very hot outside. You can clearly hear that annoying, repetitive sound. So now I am placing what seems to be the top panel. What, again? It gets easier as the box is finished. Now I have to place the party with the price of radiator like that. Just used some clamps to put the panel in place, grilled the holes, screw this cruise. And now we just have to double the baffles for both the active and the passive speaker. And right now I'm marking some guides because you don't want toe drill the pilot hole in a natural screw from the bottom. So you have to be weary of this and drilled in the correct spots. So one side this finish and do the same for the other side place. Efficient glue. Yeah, drill the holes and that should beat. Now I'm marking the holes for the binding posts and drilling the seven millimeter holes. Now is the next day when the blue dried up and I'm going to sand. Uh, holder, because this is a moment. Yeah. Now I measure to see which one is the whole for the speaker in which is for the passage radiator marking the holes. Can I have to mark the holes for the past? Radiator open off the box. Now the passive really re comes with all the weights in place. So I left him there. And then we are going to make a measurement without any weights. But for now I'm going to leave them in place. But a freshman better. It beckoned the drill and drill the holes for the two speakers. Now I'm connecting the binding posts using a small range tightened everything up. His box is going to be done in just a minute, securing the terminals. Connect the speaker first, put it in the box and after the speaker in the same place, we have to put the passive radiator. And we cannot put the box on its back because we have the speaker there. So we have toe mount the passive radiator with the box on its side. Imagine this will be a bit difficult if we have to make this place the speaker like this because we heavier 25. 5.6 Passive radiator results: So let's check the results off. Uh, the passive radi their box with all the weights in place. So what you're looking at is the near field response off the active speaker. So just like in a base reflects box, you will see a big dip at the resonant frequency off the box. So if we check the exact frequency we can see, it's at 22.1 hurts. And if we go to the night S D. So this is one with full weight, So we have to right here 0.375 This is with all the five disks in place and we should go to the box. We see that the tune efficacy is almost 24 hearts. So to hurts higher than this, uh, the only logical explanation besides errors in the parameters of the speaker and such and such, I think that by making a double baffle, especially the passive radiator does not eat so much from the interior space. So we have written that the passive radiator this place is like a 0.85 liters. Now is probably less that the speaker itself displaces this volume. So, um so actually the internal volume of the boxes, it will be a bit larger. So if we increase this fall humility 90 liters. Somewhere around that, I don't think we gain more than two liters. So if I goto 20 liters, you see the other Richardson and frequencies at 23 hurts. So basically, we are in the margin of error. And now Ah, let's try to removal the weights and do another test. - So now that we have removed all the disks, we can look at the resonant frequency of the box. So the same. This is the near field measurement of the active speaker. And let's check the resonant frequency, which is 39.51. So I'm going toe. Keep this volume the same, considering that this should be the true volume. Let's remove all the added mass. So now the reason frequency is at 39.13 which is, uh, the almost match. So this is how you tuna, passive radiator basically at disks and see how much they weigh and play with the moving mass, which basically in return place with their resonant frequency off the box 26. 5.7 Passive radiator retune: since I thought I could get away with just a single passive radio because the VD, uh, off the speaker. Actually, the VD off the pass agree? Not doubled. I have to use another passage radiator. And since I want to sell fish this box, I'm going to make another circle cut out on the top and place another passage. Radiator there now, as you can. So I cut another panel to make the double. Definitely 42nd pass. Agreed eater. And, um, right now, I think I'm calculating the diameter of the best three year to know home in inches, though I need to make the cut off. Okay, So I'm making the whole for the pain through the that board, which will be the double back off or the second best radiator. And now I have to make, uh, the whole for the best redid in one single past. So said the dip to 18 senators or 19 years. Something like that. So you cut one second one. Make sure you have power. Are powerful enough route to do this as you'll see in a moment, I'm going running difficulty, and I will explain why you think you will see some sparks. No. So much. Now what? You see some sparks over there. That is because I hit a a nail. A nail screw, Actually, because the sense that this box is made using screws, I have two screws which are protruding into my circle cut off. So probably now the knife is no good. I ruined this knife, this rotor knife. And, um, I'm thinking that maybe I can use the jigsaw because I could pass. So even though this blade is not for metal, so don't do this. And you can see when I reach the other side, and there's another sweet enough through it. So I think I could do it during the 1st 1 because the welter has taken from. So now I'm a pointless trying to cut this metal school Jigsaw. I think we've been here a blade. So right now I'm going from the other side and play this cruel and and removed forcefully removed this certain remove the pin, and now I'm going to use a normal little There we go. So now the circle cut out finished. And I'm going to make, uh, symptom panel with my probably dull blade now because the router bit went into metal. But I want to point down something over here. Since I'm tryingto selfish this box, normally you wouldn't place the speaker. I mean, he would place the too passive radiators in tow opposite panels. So place this actives great. The front panel and then the pass a great Caesar's on the left and on the right, not Don't look topping on the back because you want the to pass. A great leaders will be on opposite sides as they will cancel the their vibration. So when the speaker moves since the passive, really there's cancel their vibration Um, the box that will be more stable And in this case, with one at the top and one on the back, it will be considerably less sleep. So you have to take that into consideration as well. But right now we're I'm just trying to sell which this box, because I'm not planning on using the's boxes Anyway, they made the specifically for this course, so I'm putting the double baffle in place with clams and wait for next day for the blue to drive. So here we are next day, and I should three more clamps and make the holes for the second passive reading. Okay, it seems I have broken my Drillbit, my grill. So bread there I used metal drills because I thought I ran into a school once again. So now I'm opening up a new drill, which is actually actually for would just one fan on drilling the holes for the new passive eater. She's taking the dust out, and now I am trying to figure out how many discs I should put in place, and I wanted to away everything up. So I'm willing this thumb not which is 5.8 grams, the normal notice 3.6. And as you can see now that I'm measuring the disc, they do not measure exactly at 75 grams. So each of them has its own unique wait, which is kind of disappointing because you cannot make precise predictions using these thes passive radiators because you cannot trust the manufacturers, the manufacturer, for the numbers that they give. So I settle for three disks and now I'm tryingto make different combinations so that the total weight is the same for both the passive ragers. So I managed this 30 200 I think it's do without 236 point, 236.1. So I put that stack over there and try to find the same weight again. And there it is. And put that now I am placing three dicks disks inside tightly tighten the nut with the wrench, and then that thumb not continues on your hand. And then we have to place the the speakers inside the box. So all always start with the active speaker because it's heavier, and, uh, it's easier to put inside when the box is empty. - So now that we figured out how many discs we want to adds to the mass of the comb, let's enter the values in green eyes deep. So go to the passive ready their section. And now we have to passive radiators and you can see the resonant frequency has gone up a bunch, and we're gonna take that resonant frequency down by adding mass to the cone. And now we saw that we, um, Wade like 236 grams, including the two nuts. But I'm going to use the values provided by, uh dating audio, which is 75 grams pair, disk times, three disks. We have 225 grams. And I don't know, this is not precise. That they don't have their disks don't have the same way I'm going to use this weight. So 0.25 kilograms, And if we go to the box, the tuning frequency is 35 hertz and we can see we have a peak of about three decibels. So this is looking pretty promising. And now if we switch over to the measured results so I'm going to go to room, make you wizard. Here we have the near field measurement off the active speaker and this dip shoot the correspond to the resonant frequencies off the box, which is 31.5. And this is four herds lower than as predicted. And I don't know what the culprit here should be. Maybe the passive radiators are not settled in, so they maybe have a stiff suspension. Maybe the data isn't accurate of the parameters of the speaker. Who knows? Maybe the boxes leaky. Since I added the the second speaker, there could be a bunch of reasons, but, um What is most important is that we can measure the result and weekend tell what we have done because, as we saw in our previous enclosure examples, um, the modeling software is just the baseline and is not an accurate prediction. Sometime it is sometime it isn't so. This is the near field response of this speaker. And here is the full frequency response off the box with the too passive radiators it looks , it looks pretty good. I, my dad, for such a small enclosure. And when you see that the the overall response is lower than the near field, the response of the speaker it's because basically this red curve is in a is 1/2 space. The measurement and this one, it takes into account the actual dimensions of the baffle, which is pretty small, basically absent. So we don't get that six visible boost that 1/2 space measurement will get, which this red curves has. So you might be asking why the level difference? So this is the finished passi passive reader enclosure. The response looks quite good 27. 6.1 4th order bandpass Introduction: before. Further bent Bess is composed of one sealed chamber in one ported chamber. For this reason, a speaker, which will be suitable for a sealed enclosure, will be suitable for a poor order band pass enclosure as well. The portage chamber in front of the driver acts like an acoustic fielder and tapers off the response toward the high, just like a low pass filter. That's where the response rolls off at the low end and high end. Hence the bat. Best name. The transit response off this type of an enclosure is not as good as the lesser order enclosure I'm talking about. The sealed in the base reflects, however, it can reach high pressure levels or extend very low in the frequency spectrum. So if I open up we nicely here, we can see to response curves. It's actually the same Speaker in a band has four order band pass enclosure but tuned in different ways so you can see it, this one Over here. It extends toe the way to the low end, so like 27 herds and goes linearly up until, like, 70 hurts. So this is a wide frequency bandwidth. But if you look at the here at the magnitude is it's at minus four. Disciples. By contrast, we have this graph over here. Same linear response. But it only spans from 56 hertz to 80 hertz. So again in the frequency band, with his shorter in in the higher octaves. But if we look at the magnitude, it's plus six decibels. So it's like 10 disciples difference. This is Ah, nice particularity off the band pass enclosure because you can compromise between, uh, frequency baton band with or efficiency. If you want to sound louder, you can shorter the frequency, the frequency bad with or if you want a broader frequency response, you can opt for a less efficient enclosure. Now let's talk about the variations off the fourth or their band passing closure. You you have the single driver enclosure, which will be the most popular, and then you have some variations with multiple multiple drivers. So you have the dual driver push pull. You have the push pull compound. This is the I saw a very clothing that I mentioned in the first part of the course. Ah, we have the triple chamber in the push pull triple chamber which is basically the same thing. But, um, with one speaker facing the other way but basically the same thing. Um, I'm gonna show you how toe design this triple chamber as well, because many of you, I think I will try to do this enclosure. But we are going to focus on the first examples of the single driver. The class of the classic for formed their band passing closure. 28. 6.2 4th order bandpass alignments: if we compare this type of enclosure with the base reflects enclosure Ah, it has its own alignments, just like the in the first acoustics, one on one course. So I compiled this Excel spreadsheet to automatically calculate the different alignment you may choose. So first we have to render the parameters of the speaker. So the reason frequencies 50.12 q t s 0.13 NVs is 23.25 liters. Now, this is not the same Aziz with the base reflects enclosure. So we have to choose these two parameters we have s and we have to choose between these three values 0.70 point six and 0.5 and way if we choose zero point said one, we have, uh, zero decibels report and this ripple means that the response is perfectly flat. If we choose the other ones, we have 0.6 and we have a small ripple. This is the deviation from linearity and this one is a big bigger, which is 1.25 decibels. Also, uh, this 10.7 has the best transit response and if you go lower, you go progress. You progressively progressively degrade the transient response. And another thing you might consider 0.7 has the most narrow frequency band with it. And as you go lower, for example, 0.5, this has the most the widest, ah, frequency band And then you can choose the sensitivity. So this spans from minus eight to plus eight decibels. So in our case, we are going to go with an S off 0.7 and I'm going to choose a sensitivity. However you want to go. But judging by the dimensions of the box, if you see as is increased the sensitivity, the sealed chamber goes lower in volume and as the volume goes lower, don't know where you can imagine. It's difficult toe make such a box that will fit such a big speaker. Even though this is the net value you can imagine, there will be some limitations. So I prefer toe choose plus two disciples in the sensitivity and the the parameters off the box are already calculated. So we need 16 leader sealed chamber, a 12 litre ported chamber. This will be the tuning frequency of the portage chamber and this will be the frequency range. So from 30 to 70 pre hurts And we already know this will be plus two db also in inserted here, small calculator for the port. So if you want 100 millimeter port for each park, then you know that the length needs needs to be 800 millimeters and you can use this data toe. Enter it in Weiner SD So let's do just that. 29. 6.3 4th order bandpass WinISD design: Okay, so let's create a new project and select our driver. Best that again. Okay, So have only one driver in four order band pass. And here you can see you have different alignments proposed by NASD, and you have zero db gain with difference. Amount of ripple and minus three disciples again with different amounts of people. So I'm just going to choose a round the moment because we are going to use our own numbers name in click create. So let's go to box section. Here we have the rear chamber, which is the sealed chamber. You should write. The president was here. Okay. And this is the front chamber, which is the Porta chamber. And let's use our numbers. So we have 16 for 14 16 points, 14 zeroes to refresh the tuning frequency. And for the portage chamber, we have 12th ethers 1.9, and that junior frequency is for their 7.1. As you can see, we have a linear response. But I don't know why. In win eyes, the doesn't show at plus two decibels. We can see somewhere between zero and one. I don't know why that happens, so basically we already designed the box. So by heaven, these alignments, it's pretty easy toe. Find the correct of volumes in the tuning frequencies. And now we have toe set up the event and I'm going to use a rectangular shape with the three centimeters in width times 28 centimeters. We're going to use a slot board, so we're going to you the same dimensions and again for this band pass, we can check who the air velocity off the port. And in this case, if you go to the box, we can see the front chamber is the one which is supported. So we're going to select the front port, their velocity and, um, go to signal enter a larger value Lee C 350 watts. And I would guess he we're in the same soul. Basically, you want a lower number when you're working with rectangular ports. If you have circular poor reports which are flared at both ends like I told you, you can go on the upper side but always tried to aim for a lower number. When you are judging the airport velocity and of course you can do that by making the port larger. So if you go for four centimeters here, you can see the graph goes down, but the length goes considerably up, so you have to make this compromise. So basically we have designed the box, and now we should head over to the Excel spreadsheet to calculate that the panel dimensions . So now. At the end, I want to touch down on the subject with the Triple Chamber fourth order band Pass. So let's switch to transfer function magnitude and the this is easily enough. Let's switch to a circular port because it's easier to comprehend. So we have, ah, four inch port, this 10.2 centimeter and the length is roughly 85 centimeters. So let's switch back to the box. In first we calculate like this, like with a normal single driver. One sealed one Port it cheap and we have Ah, this which is the seal volume and this which is the port involved, and the twinning frequency and the just imagine that we are doubling this enclosure, so we have the same volume for both the steel chambers. Now we have to seal chambers and they both have 16 for 14 leaders off volume and the ported chambering the mental it's actually shared, and it will have double the volume off. Normal one sealed one party chamber enclosure. So the chamber in the middle will have doubled the ported the chamber volume so 11.99 times to we have 23.98 leaders. And the fact of the matter is it will have the same tuning frequency. But since, um, the chamber has a larger volume, the event will have a different size. So to check the new size of the vent just but make this volume double so 23 points, 90 date putting some zeroes just and keep the same 20 frequency. And when you go to event, you can see that the the length of the event has bean reduced. And now this is the new, uh, port length. So you have the same volume for sealed chambers. The porting chamber has doubled the volume and event has this you length to keep the same tuning frequency. And this is the way you make a triple chamber for order Band pass. And if you look at the frequency response curve here, it's not that one. You have to go again to be living for 99 This will be the This will be the actual frequency response off the triple chamber. 30. 6.4 4th order bandpass Excel spreadsheet: before we start to calculate the panels for the four for their band pass enclosure. I want to make a slight modification because, um, I built I am actually ordered the dimensions of the panels beforehand. And then I realized that there is a problem because I calculated the dimensions with the magnet facing in the sealed enclosure. But you have to understand that in a four further band pass, the speaker is encapsulated in the enclosure, and if you want to pull them the speaker out, you you have to destroy the enclosure somehow and to make my life easier. I made this panel removable, but if I had placed the speaker with the magnet in that chamber, I could. I couldn't remove the speaker, so I need to face it with a magnet towards the the port at the chamber. So that's why I had to make some slight modifications to the enclosure, and I tried the to maintain a linear response and let me open United's theme, and this is the new response. So basically, the shape is a bit the narrower, so the frequency response band with is just a bit in their or and a bit higher in them magnitude. And, ah, he wrote of the volumes in the Children frequency. And now if we head back to the Excel spreadsheet, I'm going to show you in just a minute that them the extra things because it's a bit different compared to the other, likes other Excel spreadsheets. So way have the thickness, which is 18 millimeters and let's interest the numbers here. Seal volume 16.1 16.1. Seal bracing We don't have any bracing in the sealed chamber. Let's see the port of Volume 16. No bracing in the portrait chamber and the speaker. Displacement is 2.1 liters and the event dimensions 200 180 millimeters communicators. We whipped and lets the length 635 635 And now, uh, I'm not going to use a double baffle, and here you can choose where you are placing the magnet off the speaker. In our case, we wanted to be in the ported chamber because I have to remove this panel and pull the speaker out this way. And now all you have to do with site. The height is calculated. The according to the dimensions of the pork. But, um, we only have to enter the depth so it can calculate the width of the enclosure with the designated volumes. So let's go for something like, I don't know, 325 millimeters. So this is the external with off the box. And here we have all the Penhall dimensions. And since this is elaborate bots box, we have no second port panel. So this is not placed over here on Lee to full size first council. This and this and that is our labyrinth port and something extra to maintain these volumes . The correct volumes. You have to place the powerful into the correct position. So this is the whole length off the the bottom panel and you have the different dimensions . So the sealed chamber has to have 199 millimeters in this from the width of the box. And this is the bear ful 18 millimeters. And this is pretty much straight for so you know where you are placing this panel. So the volumes off the enclosure holds true. So this is basically a top down view off the enclosure and now that we quite easily calculated the panel dimensions with can go to sketch up and actually designed a three D model off the enclosure. 31. 6.5 4th order bandpass SketchUp: So now let's start to build our three D model into sketch up. So let's it, our units that and let's start building. So let's start with the bottom panel. 28955 Let's make it again. 589 I don't know why it places it like that, but we are going toe rotated. So let's make 18 millimeters. Let's make group. It's grow teeth. This just like that seems like a long battle. The images did this correctly. Nope, it's I don't I don't away something way. Sometimes this happens. So 555 to 89 55 to eat. What is this? He raised rectangle. Click five, 555 So now is correct, I think, because I used dot instead of a comma. So let's push pull this 18 millimeters make group, and I think now I'm going to start with Beneful. So let's go with the baffle 289 to a zero. Embrace the arrows like that, I think nine zero and let's push pull meters, and now we have to make a circle cut out in the mantle. Have a circle, both 15. Just like that. Now delete other lines and Bush Bullis go to the other side and now we're gonna make this group make. So now that we have the baffle, we are going to have to put it into the correct position. So we have 199 millimeters away of from this edge. So first we gotta mark this spot, Let me switch to top down view, and we're going from midpoint 499 millimeters like that and like that, that's Thetis. And now we have to place this panel right beside that line. So let's move it over here. So that is the correct position off bare ful now, I don't know. No, let's make the sides, uh, you have to realize that the left side is different size compared to the right side. If you see this one is between the front and back panel and this one sits on top off the front and back pack. So the sigh, the dimensions are different. So let's start with the left side. 3 to 5316 So we're tango looks. Brick Tango 35316 Select us to push bullet 18 millimeters. Go ahead and make group. Let's elicit correct position. Now I'm going to leave it on the side over here because we have to place the front and back panel tool um, sliding into the correct position. But for now, let's make the right aside. Toe 89 to 80 Okay, zero. And let's push. Pull this May group and place it. Grab the other end and places in the correct position. And now we have to make the port. Let's take a look at the port. We have two panels. 259280 Let's make the panel's first 90 push. Pull these 18 millimeters and make group. Is this the correct size limit chick has slided into position? Yep, looks about right. Let's slide it over here because the port these 13 there's wide and we have to market like that. And now that's pleased this panel in place. Dooley the slime and go ahead and mark another one. 30 millimeters Go down. Delete this line on let's click this panel and move it by holding control to make a copy. And this one, we have to place it on the other side, just like that, and delete this line and this oneness well. And now we basically have the port in place. So now we have to make the front and back panel 316555 So six millimeters. Let's make group and let's rotate it like that. Let's also make a copy, my holding control. And now we have to Let's think this over here and let's exploded because we need to make a port. And let's draw a line from the middle 18 millimeters thickness off one panel and we have to go up dead like that. Authorities 30 millimeters and have to go 18 millimeters like this and like this. Oh, check it first. I think so. This is 30 millimeters. This is 23. Well, this is 20 free. I don't know. Let's do this again. We want 17 millimeters just like that. So I think the top one is incorrect as well. So let's punching 18. No, no age millimeters. Correct. And this should be 18 as well. Yep. And now we basically have to deal the extra lines. I select this face and but Bush bullied on the other side and we made the whole for report . That's May group on. Let's drag it into police. Something doesn't look right. No, it's much better. And this panel should be into the back. Just like that. Gonna put this one in two places? Well, no. Zo mean, actually. Have to plead the other corner like that. Perfect. And now we simply have to make a copy off the bottom panel. My holding control. And we have to place it on talk just like that. And this is our box. And for the sake of it, let's measure the the length of the port. So I'm gonna move this front panel out of the way on. Let's start measuring. So I'm going to take my crayon and mark this Take the midpoint, Go on to the other side. So from here, I want to go 15 millimeters down. Go on the other side. No, again. 15 millimeters in goal. Only way to the other side 15. Let's Mark and we're here. So from the 15 millimetre point going to there. So let's delete of the extra lines, right? And let's kill little length. So let's think this tool we have, like this agent millimeter from the baffle plus All right, 274 plus 48 plus 259 close. How much is this? 33. And if we check the Excel special, we can see that the length should be 635. But we ran into that same wish issue. If I start to increase this length like six, other than 45 50 I still do not the get the second panel because yet you can see it should be 662. This is the time where we start to add another panel and the length goes up considerably. So that is the problem with this Lambert style of rectangular ports. When you reach the edges of the enclosure, you are forced toe fix the length. So it seems like the calculator is working correctly. And like I said, if you find any bugs, please let me know what have you found so I can fix the Excel spreadsheets 32. 6.6 4th order bandpass build: I always begin the four for the band. That's build. So right there, I drove the diagonals for the baffle. But I'm not going to start with the circle cut out. I'm just going toe Mark. Firstly, I'm going to mark the position off the baffled. So I know where to place the panel and also where to place the nail gun on the other side. Because we are going to use a nail gun now with Brad Nails. This process should be more easy, but you need a nail gun in a source of compressed air to do this. So this is the position off the baffle on both sides. And now I have to mark the position off the port panels because we have, ah, labyrinth, the style pork. So this is going to take a while because, um, it's more than one panel brought up a smaller ruler to make my life easier. Flip the channels because I have to do the same on the other side. Almost there. I think that's this is the last mark. Yep. No, I'm drawing the lines. Same on the other side. Now I'm going to make the circle cut out for the wolf for so I make a small hole in the center for the pain. So in this case, when you have a very small panel, you don't have any room to fit any clamps to hold your panel in place. So how I'd like to do it is to hold the rotor steady and move the panel instead. So you can see this in a minute. Just like that, Hold the rather stadi and carefully knew the panel until you finish the circle, flip it on the other side and doing other pass on. That should be it with a circle kind of, and we have to make the holes for the screws at the moment you don't want. I don't want to do this with the boxes already finished because it's going to be a cramped space. And, uh, it's going to be more difficult to fit the drill inside that small space. So I'm going to do the holes right now, so we don't have to worry about them later. And then I reduced the speed so you can see clearly what I'm doing when I'm assembling the panels. So we're going to attach the panels that by step. So right now we're going to attach only the front battle with the bottom panel. So Justic play some glue on Lee on that side and used the speaker Baffle has, ah, 90 degree tangle. So, you know, we are placing the panels in the Grix fuck and just punch in to nails. And then I had some more easy enough has put the side panel place and blue make sure it's in the correct position. I'm just using some scrap India, so I know it's placed flush. You don't even have to hold the panels in place that those nails are that fast. Make sure you have enough air pressure because if you don't have enough, the nail won't go all the way through. And that is not good. You It's very hard to pull the nail out if it doesn't go all the way in and you have to clip it or something like that. So now I'm starting to place the first court panel, and the second panel will be on the other side, so I have to please the back panel first. But when you place the back panel, we will attach the bear Feliz will. So I'm placing Grew into that position. So please the bear full also. But that's the back panel. And start shooting some nails. Take your time. They see you really have to do those markings correctly because if you are off by, I don't know what centimeters and one centimeters and the nail doesn't get the baffled. It will stick out inside of the boxing, maybe clip your speaker and do some damage. So make sure you punching the nails into the correct position. Now I'm taking this opportunity to place some more wood glue where the panels meat so the box will be airtight. Now it's time to place to place the last port panel, place the glue in the correct position, align the power correctly and then get your nail gun and watching the markers with which I made with the Cran. So I know the Panelists is in the correct position and then fix it in place. Now all that's left is the top panel because the sigh we will leave it after we have placed the speaker inside place. The top panel I'm using the guides on the sides know where I'm placing the nails, but just be sure you're see, you're seeing in a minute bring a ruler so I don't miss the nails. Just using the ruler is a guy finish up with some extra nails. And I did this opportunity to place the more would blue inside on the top panel because I think I'm going to do that in a minute. I'm just cleaning things up, placing some clams. Why not? Yes, it's not meant. Three. You see it now I'm bringing my junkie gloves, and I'm going to place some glue on the top panel because the rest I already placed extra group. And this is the next day when the glue dried off, taking the clamps off. So making a big hole to where the porthole should make sure you don't really on the other side. Make sure it really from the correct side because you might get confused and then you practically ruined your box. There have had a moment of anticipation. I thought I didn't, but it puts actually correct. So no, the porthole is done, and we have to get over debris out. Now I'm making the holes for binding post, and this is a mistake. I realised afterwards the whole truth, that being made on the on the back panel out in front. But, hey, we make mistakes. He's not gonna take box performances. Just looks awkward with the binding toast center front, You can only place them on the back because on the side it's the pork. And on the other side, you don't have access to the terminals to the speaker terminals, so the only correct position would be on the back. So now I'm now I'm drawing half way on the MDs, so I know where to drill the holes correctly. So nine millimeters in and I admire marking the holes because this pals, this panel will will fit to the box using screws and silicon, because we have to make sure that we have some ways off getting the speaker off and this will be it. And after we measured the results, I will show you how I'm going to remove this panel and get this big girl because you condone this. You have to destroy the box on some if someday you want to get the speaker outside the box . Because that is one of the disadvantages of the band passed boxes. The is not easily removed. So now I'm getting the new sending people on people's faces Just a minute. And now I'm attaching the binding boasts and connecting the speaker. We already made the holes. Excuse me into the baffles. From now we just have Screw this, Kareen. I'm getting the nails in the correct bit, placing some silicone between the two panels so we know that they are sealed tight point. And now align the panel with the holes in place, all the screws in place and Screwem one by one going, going pop first. Then I'm screwing them all the way in different positions until the panel is secured to the box. Then I realized that there is quite a beautiful get between the panel in the box, and I want to make sure that it is airtight. So I'm going to place some extra silicone from the exterior right inside that gift, and that should be it 33. 6.7 4th order bandpass results: Let's interpret the results for the band pass enclosure. The fourth order one. So before we check out the measurements, let's look at them model frequency response. So this is the response with the modifications I have to made the I had to make to the box since, um, I have to place the speaker Thea other way around. So I have some way off pulling the speaker out of the box. So this is, um, our model frequency response. So a bit hung bish, So to say, narrow frequency response. So it's linear from 60 down to 35 late. See? So from six. Let's go like this, minus some disabilities. So 65 2 35 in a linear fashion. So this is the response we hope that we achieve. So if I open up broom que wizard, we can see that the responses not quite like we calculated. So it goes linearly broader look like, let's say, 75 herds and down to 30. So the frequency response is a bit broader than we calculated. Also, we have this annoying hump on the lower end of the spectrum. So, uh, there is no way off telling them the resonant frequency off the ported chamber from the frequency response chart. Because we can only measure the port near field. We cannot access the speaker because it's inside the enclosure and we cannot measure the speaker near field. Instead, we can make an impedance special. And if we check the impedance chart, we can see that the resonant frequency is a roughly at 40 hertz. So if we go back to win eyes, the we can see that we aimed for a tuning frequency off 47 hurts. This poses some problems because we made bricked angular port which we cannot alter after we made it. But if we would have used ah circular port, we could've remove it from the box, cut it to size, and then place it back again and make another measurement of the box and CEF. That is what we are after. So if I place here 40 hertz, I think you will find this response similar. Toe our measurement. It's broader and has this hump ato lower end of the spectrum. So it's always best to have measurement equipment because you know what you're actually building. So in this case, if you use the circular part, you would make it shorter in and try again because this band passed enclosure are very sensitive to two errors. And but, like I said, if you could measure the result, you can go step by step until you reach your goal. So now let's consider the box finish. And let's take the case that you want to get the speaker out of the box and I'll show you right now how I removed the speaker from the box so they start removing the screw. This will take because there many of them, but they come out pretty easily after that, just get a sharp blade and start cutting between the panels. Put the box on its side if you find it easily and be careful when you reach towards the end toe, apply less pressure. Otherwise, ah, you can stab yourself and get injured so basically opens up. That's it. 34. 7.1 6th order bandpass Introduction: Let's make a brief introduction about the six order band pass enclosure. So this is one of the most difficult enclosures to pull off, and you rarely see this option picked Not much literature out there about this enclosure. So if you want to find more information, prepare to be disappointed. And, uh, since I didn't find any alignment stable when we're going toe design the enclosure, we're going to go blindly and play with the numbers. Maybe there is some alignment stable out there, but I couldn't find them. Bose is the company which patented this design so no one can make it commercially. So if you see 1/6 order banned past enclosure made by a reputable manufacturer, it's Bos. Uh, but, uh, if you make one for personal use, there is no problem in that. Just that you cannot sell it in the large numbers things type of an enclosure has the potential to go very low and very loud for the amount of volume you invest in it. What do I mean by that? If you take, for example, a base triplex enclosure with the same amount of volume, it will probably not go that low or that loud or both. It's going to be a big enclosure nevertheless. But if we compare the same amount of volume you were, you will get better results with this type of enclosure. The downside is that you will have, unless good that transit response. So this is this design is just like the fourth quarter band passed. But instead of one sealed in one ported chamber, you have to ported chambers and let's see how how this these type of one enclosure looks like we have two types off 600 band pass enclosure. We have the parallel sixth order band Pass, which is the most common, and this is what we will use as an example for this course. And we have the serious the Siri's sixth Order band pass, which has these cascading ports. But these air less popular and more difficult, constructed in the Parral six tartar. So let's go ahead and try to design such an enclosure 35. 7.2 6th order bandpass WinISD design: Let's start designing 1/6 order band pass enclosure and, uh, start denies the create a new project from that select our driver, the jail audio and one driver sixth order Band Pass enclosure. You see, we nyse the Onley, Hezb, um Carol uh, arrangement. And, as you can see, a normal line, what is available for 1/6 order? Banned best, But nevertheless, let's start the project. That's name it BB six, and we have to report it chambers. So we have to choose the volume and the tuning frequency, and you can see the response looks terrible. Just got some random numbers over here. So now the only thing you can do it's, um, basically, you have to play with the numbers and hope you match with something that resembles a good response. So first, just simply play with the numbers and see how it affects the frequency response. So if I increase the volume of the rear Jim, where is Goto? 50. 60 70? Let's start with tuning this to a lower frequency. Let's say 20 and this one toe a higher frequency, so let's say 70 hurts. I don't know. And, um, when you actually tuned the frequency, you might be them to say, Hey, I'm I want really high outward at a certain a certain pregnancy. And I'm going to tune both chambers at that exact pregnancy, and that creates a problem. Let's see if I kid here 20 hertz, you can see this. We're going crazy because, yeah, the ports. If you tune into the same frequency, the ports are out of phase in the frequency and they were will cancel each other out. So you are actually doing more bad things. Good. So we can see Now we are getting close to her response. That looks more normal. Let's see what happens with we increase this can before we're going into the right direction. 25 the We are trying to get a linear response. So if I if I get this hump lower, that would be great. So if I increase this 30 goes up, let's turn back the 20 and tried to reduce the tuning frequencies referred 60 Hope Sevens like we are going into the right direction. So 50 No, this is looking pretty good already, and, um, lives tried to make it. This is looking pretty good if I increase this 30. So this looks pretty good. We have a ripple off around, I don't know, one decibel. And the response is pretty linear from, like 27 to 60 hertz, which is great. And if we take this charters reference, we can see the responses plus four five TB, which is pretty good. So now, uh, we can we can design this enclosure using this these numbers. But in reality, when I first unit, I am, um stop at the following number. So 70 litres here, 27 herds and 24 liters here and 47 hearts. So basically, this is a bit higher in volume, So now we are at plus five decibels. Uh, what I'm basically done is narrowed the frequency response band with in increase the efficiency. Just like we learn, um, at the four for their band pass. It applies here at the sixth order, banned best as well. And we are going to go with circular ports so we can tune it afterwards because this is going to get really difficult. And you can see, even though the sixth Order is more difficult toe building 1/4 order, the fact that we use circular ports and did incremental measurements and modify the modified the ports we reached. Ah, a nice frequency response even better than the four. Further because that one we couldn't tune it anymore since it had a rectangular port. So it will have chance centimeters in diameter. So these are the port lengths 38th and 37. And these are the volumes and the tuning frequencies. No, We can also go ahead and check the poured velocity and increase the signal toe 30. We can see it's pretty high, so we can expect to have some Portnoy's this chick of the other port. This one is a bit better, and you can see dipping over here because this is where the energy is taken by the other port. So if I switch over to this one, the peak should be right that this def And this dip over here coincides with the tuning frequency off the other port. So basically, we're going to have, uh, some shopping here over the at the lower frequencies somewhere that 26 hertz 27 where the second port is tuned at and you could try to put you could try to put a larger port, so 50 centimeter and you can fix this, but the length is pretty absurd. So I'm going to stick with the A 10 centimeters and accept the fact that that I will have some some shopping at that frequency. So basically, this is the design. And now let's switch toe the excess appreciating, calculate the panel dimensions. 36. 7.3 6th order bandpass Excel spreadsheet: So let's begin calculating the panel dimensions. This is a bill which I did a while back, So I'm going to use it as reference. I'm not going to build the box again, but I'm going to show you how I did it. So in this case I used the 22 millimeters thick MDF. And now let's punch in the numbers. The volumes of the enclosure. Excuse me. So let's open United's D. We have Ah, sit. Is the smaller chamber. If you look into the image, you can see the left chamber is smaller. So here we are going to introduce the data from from the front chamber called Here in Weiner is the so 24 liters and the bracing. We have no bracing and, uh, the right one 70 leaders, 70 litres and on the right chamber, I actually do have a bracing it is not the shown here in the diagram, but in the actual build, I place the panel for bracing and, uh, I don't know, might be like two liters or something like that. So I am going to enter an estimate number and the speaker displacement. We know to be 2.1 liters and now the lift port diameter. Let's go toe when I see this is the front chamber. So from chamber is 37 said Dimitris. So 370. Uh, I actually like this, huh? We have the diameter of 100 the other than 70 in the length, and the diameter for the other one is still 100 and the length is 387. 386. We have a double baffle. Yes, I use the double baffle. So this panel over here, it's doubled, and the magnet is in the bigger chambers on with the one from the right. So select right. And we will pull the speaker over here from the small chamber when we want to get it out of the box. So we put a lot the numbers. All we have to do is input the depth in the height, and now, depending on the place you want to put it. I, um uh measured the box for the trunk of my car. So I entered the height off 300 looks It seems like that thistle is protective, and it shouldn't have been Okay, fixed it. So this the height was 334 okay. And the depth I, um um measured the death to be some around 554. So the calculated width of the box is 789. And, um, these are the panel dimensions. And in this diagram over here, just like, um, in the fourth quarter banta section, it tells us where to place the baffle. So we get the correct volumes in them, the rock in the right and lecturing. So you can see the Bethel is 44 cents is a It is a double baffle in one buffalo 22 millimeters thick. And you have to place it 181 millimeters away from this age and 520 away from that age. And then your volumes will be correct. Another thing I want to point town is that for the other enclosures you, um I usually placed the sides inside here, but now I place them on the exterior. So I made them a big bigger have to take this into account because I want them to be removable. So this one and this one have the same position on the exterior, so that should be about it. You you should check if the board length is not too big according to the depth of the box. But we can see that that is 550. And the port, the longest one is 390 roughly. So there is adequate room for the port inside the box. So basically, this is it. These are the panels. And let's goto sketch up and make this a three d model of this box. 37. 7.4 6th order bandpass SketchUp: so I don't know that you have that kun. Probably okay, Not great. Um well, you know, I have influence seven for the problem. What you for Trump? Local folk. Look, you want to kind of this car in order to decide with just one thing going to happen? What e e e o t allege that pretty. And I have got to go toe to toe. Like if you can tear cat Qatar from point a second. Because the fact once, uh, it is going to miss that went girl. Yeah, I'd like of you, Mrs. Never mind. That's what about this. Uh huh. E we're all about for African engines. Problem to Putin. E trouble from you. A lot of criminal, Just about kind of credible, a lot. And the and it's draw the circle cut out in the center. The radius is 135 millimeters And it let's delete the extra lines and push police to the other side. And this is our double baffled. Now I have to make this a group, and now we're going to move the front, careful out of the way. And, uh, let's put the front baffling to the correct spot. So, uh, we have two places, 181 millimeters away from the left edge. So let's take our pencil. 180 millimeters. Let's draw some guidelines. Delete this. Select the baffle and places like that. There we go. Now we can place the from careful onto the correct place. Seems like it's not. There we go now. Everything's looks fine. We can see we have a room for the port. This is nice about treaty three D modeling. You can see if we you done it correctly or not. So now we can make a copy off the bottom panel in place, don't talk, told control and move it and select the top corner. Music like that looks correct and now have to make the side so the sides are 55433 in excess. Plan for three before push, pull this millimeters and, of course, select everything and make group. And it's to mark this position. We have to grab the other corner because some top like this, whose only interview having difficulties like that and it fits perfectly, then hold control more with once more to the corrects But can there we have our box? This is our finish box. This is how the sixth order banned past box should look like. 38. 7.5 6th order bandpass build: so the sixth order banned best box. I haven't actually built it right now because I already done it in the past. So to give you a bill guy time just going to follow the article I wrote on your judgement that come and let me zone this a bit and you can find here the panel dimensions and, um, the only thing that is different is the with because I entered the volume off the brace on the fly so that skewed the with a bit. But, uh is just for a reference, not the actual numbers. So in this bill, guy actually created some grooves for the baffle and for the brace. So here we can see I aligned the bottom and the top panel because you want the grooves in the same spot. So when you put the panel there, it stays in place and it's align correctly from the bottom to the top. So, uh, this is, um ah, you saw me in the enclosures I made before I just draw lines on the I just roll lines on the panels and try tow, line them between the drone lines. But here, when you have a groove. Let me show you how I made the grooves. I used this guide for the router and made the first pass. I simply this'd ism, I think eight millimeter robbed orbit. So you go eight millimeters like this on the beginning of the group and on the end of the groove And this, you simply use the router by hand by Freehand and cut what is in between. And this is how it should look like. Of course, the baffle and the breeze have to be a bit more bigger. So they fit Minto. These grooves you can you need to compensate for the for the depth of the grooves. But it's nice that the panels sit nicely. So here is the, uh, bottom panel in the top panel. So the grooves are in the same spot. And here is how this is the double. Therefore, so here is how it fits into the groove. It's a nicer this way, but it's a bit more work. So this is the double baffle. This is how I made the double baffle. Okay, this is the front baffle where the ports will be and you can see here this panel I used for brace for brace and instead, off rectangular cut out. I don't know. I just feel felt like I going to cut a circle. But you don't fit any speaker in here. It just made the big hole so the air can circulate freely. It's basically a brace, just like the rectangular cutout brace. So I applied blue and place the panels. So here is the baffling. Here's the brace. This is the small chamber, and this is the bigger chamber and, of course, apply glue to place the top panels. Will and I left the sides to the end, of course, because we have to drill holes and use silicone. So I'm going to place the terminals on the panel, which, which is on the, uh, bigger chamber, the and the you can see here. I fit the the binding posts connected the wires, and, uh, for that panel you can apply glue. It doesn't matter. But on this side you have to apply silicone and use screws so you can remove the speaker afterwards after, uh, otherwise you have to destroy the box or something like that. So now I give instructions on how to make the ports. So here are the pipes and here are the dimensions with the flares. Play some silicone on the port and place them inside. And then you have to wait until the other day, Clear up the excess silicone and this is how it should look like no off course when I, uh, reuse the this enclosure the panel was off. And of course, one port was off as well because you cannot pulled up speaker out if the port is in place and I have to reversal that and I can show you a clip right now off that process. So first of all, I'm trying to remove the excess from the site because I want to apply a fresh batch. So everything box. Oh oh, and firstly, I have to connect the speaker so cunning the speaker Throw it inside. Now, before I do anything, I bring out the multi meter because I want to test If the connection is good, you don't want to seal everything up and then notice that the connection to the speaker is not good. So now that the connection is good, we have to fix the Wolfert to the careful I was placed support inside. I'm not going to place any silicone between the port and the box because the old silicon has talked with the bucks and I'm just placing it on top. And this cruise will will hold the port in place. But it will not rattle because it has that old silicon between it between it in the box. So make sure you don't over tighten because my braid break the plastic from the port. It's secure in place. Now I have to put that plan alone. But before we put it, have to apply silicone. So the same process. I'm placing more silicon. Now, you see, I'm making this zigzag mobile because this is a thicker India 22 millimeters. So that should cover it. No, Put the panel correctly, make sure you don't place it, uh, upside down because then the holes won't fit. So placing the screws and then stops Group see, the silicone was enough. She's a good sign now, wiping the excess off. Switching to my Jenkins, my junkie gloves. Him what Texas. And that is it 39. 7.6 6th order bandpass results: Now let's check the results for the $6 band pass enclosure and let's start with frequency response charts. Here I have the near field measurement of the ports. And when you measure, uh, for example, this one this is the port, uh, in the small chamber. And, uh, you can see that the risen in frequency is that actually, it's not the resonant frequency off the small chamber. This dip signifies the resonant frequency off the other chamber. So this is actually the resonant frequency of the big chamber 25.6 hertz. And if you look at the other port this one, the one in the large chamber, this will indicate the resonant frequency off the other chamber. So the smaller chamber at 46 0.52 hertz. So if we check with the green Eyes team, we can see that we were pretty close and very mind. These are circular ports, and I did a lot of trial and error until I reach these numbers, because if you don't have a way to measure your results, you don't know where you're at, then you're probably lucky. You manage on your first goal, you have to measure and make a judgment adjustments until you reach the correct length for the port. So let's head back to room accuser and let's look at the overall frequency response. So when we added the to ports together and when we, uh, subtract the baffle diffraction because that that's why the overall response is lower than the individual response because these are basically half space measurement in this is not we compensated for the careful and let me close this up and you can see the responses pre leaner. We have, ah, variation off. Well, you know, like one, maybe two disciples, which is great for this type of an enclosure. So, um, that is because you can actually feel more and try toe rich better linearity. But I'm not gonna do that. In this case, we can see that this one is that 25 hertz and this one it's almost there. So if I punching here 25 words, you can see the similarities in the curfew. We got toe, um, a bit of a slope here and not not so much senior, just like in in this example. And if we check the impedance shot, this has three spikes because we have two resonant frequencies here at the lowest point between the peaks. So we have 25 Hertz prison frequency frequency, which is correct. It is this one over here, and this one should be 46 and we can see it's actually 4 to 2. So bear in mind when we were making electrical measurements like this in peace and impedance measurement, um, you will get the corruption from the coil off the speaker in the accuracy of the measurement in this case, the resonant frequency off that particular chamber has some degree off error. If you want higher accuracy, always rely on the acoustical measurements. So that is basically our sixth order band pass enclosure, and now we should go ahead and test them head to help. 40. 8.1 Box comparison: So we're going to start with the sealed enclosure. Onda, you can see this is my daily driver enclosure. It's a fiberglass enclosure. It's actually smaller than this one because it has two feet over there. Uh, so, um, the Q t c is actually a bit higher, so this will have ah, more linear response. Now, I have set up this multi meters. We're gonna, uh, fired them up right before we are going to make the measurement. Because if I turned them on now, they might shut off because of too much idle. I want to shoot something in the car first, So let's close this up. Okay? So the first thing we're gonna go, I'm going to show you what we're going to use to make these measurements. So normally you will. You will you use, um a sound pressure level meter. But since I don't have that, I have something else that will work just fine. This is an Earth Works microphone, and it's a bit more expensive compared toa your run of the mill measurement microphone. But you pay extra for, like, three things. So this has ah, broader frequency response. It has, uh it goes down toe, I think five hertz and, uh, all the way up toe 23 kilohertz. It also has a very linear response compared toa other cheap microphones, even though it comes with the calibration file. And, uh, what's more important, the this goes up measures up until, ah, 140 decibels. So your normal microphone will start sleeping in 130. I think this one starts to play up about 142. So since our enclosures will not exceed 140 decibels, we can use this microphone just fine. So to do these absolute measurements, first thing is to get the appropriate microphone and second, we need to calibrate it. So I'm gonna show you how to do it Just a moment. So let's hope this upper toe over audio interface and let me bring up just a second, because we need a tiny adapter. So we have to fit this to the microphone. And now let's bring up the sound calibration device. Now, uh, this emits one kilohertz stone at precisely 94 decibels or 114 disciples. So, uh, what you do is actually ah, place it in the slot over here and you can see how it fits quite snugly over there. If you use the title in audio microphone, you can see that it goes inside. But since it does not have this adapter eat the licks sound. So your calibration will not be that accurate. Actually, it will be very inaccurate, So don't do it unless you have these perfect seal. So we go to SPL meter after you set everything up in a room, make you wizard, and we have to calibrate So select this calibrate and we have to use an external signal in click. Ok, now it's way. Let's turn on this. Uh, now it's a meeting of 94 disciples. Don't you don't hear it because it's actually inside. If I hit the 114 you probably will hear it. You still don't hear it? Let's live it to 94 decibels. Let me turn on the Phantom power because I didn't see any any movement over here. So now we are telling roomy que wizard Hey, this is 94 disciples. So let me shut up for a second Now, as you can see, the maximum spl with this calibration is 100 and 29 disciples now. This means we can we can we can measure. This means we can measure accurately up until 129 decibels on. This is no good. We need to go up until 140. So what we have to do is lower the gain on our audio interface over here. So let me let me turn down the mike just a bit. Remember, if you have the focus, right, Scarlett, even if you go all the way to the minimum, you can still go up until 130 decibels or something like that. So I use these personas audio interface. It uses external power. So I have this tentacled death there. Over here. Now, let's do the calibration once again and see, uh, see how far we can go. Now you have to understand, these are very high sound pressure levels, and you are going to easily click the microphone. So you have to turn down your other out your interface. So let's will use the external signal on before dispose in your case, See, we can go now up until 100 and 50 decibels, which is great. So let me close this up. Let me You can hear the sound If I go to 114 it was even louder. So let me Doesn't want to go on to say I want to shoot. I want to show you what happens if I Okay, that's that. Let's put it back again and let's hit 94 decibels. We should get a reading of 94. Here's the live reading. So when I hit 114 it should read 114. Now we can see we are reading a 113.9. So, uh, you have to understand that this is ah, class to you can see over here it's a class to measuring device. This means it does have a slight error, but the 0.1 disciples is barely nothing. There is ah more accurate calibration device Class one and I think above class one it's like a laboratory grade or something like that. So now that we have calibrated the microphone, let's put it on the microphone Mount over here. I'm gonna leave it on the dash like that when we're doing the actual measurement. Now everything is calibrated. Onda, uh, I want a full screen this and we have to reset on meters. Now, before you make the actual measurement, make sure you have this on fast and you have zid waiting. This is the weighing off the microphone. If you use a or C, you actually apply some custom curves to the frequency response of the microphone, and that is definitely not good. The said weighing excludes any obstruction with the microphone. People see response. So make sure you use the that way. Okay, everything is set up now, huh? I'm going to use actually on Ah, sweep from 20 hertz toe 55 hertz. And, uh, the volume I chosen is something a bit lower. I don't want to stress my support for very much. And also, when you are judging the actual disciple count, you have to understand that this is a big sedan when you go to those competitions, everybody was just small cars because the support for radiates into a smaller space. So the score will be higher and also bear in mind another factor. Uh, the rear bench doesn't fall. So the only way the trunk communicates with the inside cabin is that that is actually not a ski pass. I actually made a hole over then and use the middle grill to mask it up so it doesn't look awkward. And that is the only way the trunk communicates with the inside of the car. So you have to understand that that bench will somewhat dampened the overall result. So it doesn't matter the actual score. We are interested in Onley comparing the enclosures between each other. So now that we have everything set up, I'm going to set up the multi meters way can see how much power we are feeding the subwoofer. So I'm gonna set this volts a C and said the range accordingly in, uh, select maximum hold and again with with the clamp meter Max, hold on. Now I'm gonna shut the trunk and we are going to blast things up so we can see how much decibels we are reading. So let's Ritz reset everything. Ah, the volume is said Teoh. I also have ah volume control for the amplifier over here. And if you can see it, it's set in such a way that I have to go to the maximum from this knob. So for every measurement, I will go to the maximum from this knob and do and see how much streets. So this is already life. So let me go all the way to the exit. E wanna let it run one more time? So we have 123.5 decibels? No, let me check the meters so we can see how much part where we So we have 25.9 in 9.9 camps. Uh, take on the calculator. The main strange point mind times 9.99 roughly 250 watts Way. - So now that the circus music is over, let's judge our results. So let's start with the less complicated enclosure. So we the sealed let's compare the sealed with the base reflects with the linear response because these two enclosures compared directly because they both have the the Q B three alignment. Even though the bass reflex is twice as big. Let's, uh, disregard this factor. They are relying toe have the maximally flat response, and in theory, the theory is that the base reflects enclosure is three decibels louder than the sealed counterpart. So now let's compare the frequency response. If we look at the seal curve as we expected, burial in your response a shallow Rohloff curve. And if we compare it to the base, reflects, we can see that the base reflects extends mawr into the lower octaves because it's a bigger enclosure and it's tuned in such a way. And if we look here around the 34 hurts Mark. Because, uh, we know that is the reason and frequency of the car. The drink, the distance between two, um, is seen in the difference between the SPL measure. So let's move on to the next enclosure and let's talk about the base reflects higher. Um, what is curious here is that I expected a larger number than 131 especially if I compared to the sixth Order Band pass, because that one is even louder. And this is even more curious because, yeah, the sixth order banned past will play low and will play loud. But this high output based reflects enclosure was designed specifically to go really, really loud, and them I started toe dig into this the subject and, uh, I found an explanation. This is how my trunk looks when it's empty. So I'm pointing out that hole in the middle because that is how the trunk communicates with the inside cabin and let's see how it looks with a normal size enclosure. So this is the for former band Pass, and you can clearly see the hole in the back. No obstruction here and let's go to a bigger enclosure. This is the sixth order band pass, and even though it's a big enclosure, you can still see the whole. There it is. It is not the obstructed. But when we switch to the high output based reflects enclosure, this one is a bit taller, and you can clearly see that that hole is obstructed. And that's why the score is lower for this enclosure, even though should have been higher. So as you can see, that is the reason why the base reflects didn't perform better than the sixth order band pass. The sixth order banned Best didn't obstruct that hole, and the pressure could go inside the cabin where the microphone waas. So, um, but let's look at the frequency response, and if I take this base reflects. You can see this huge peak. The difference between this and and the normal based reflects. It's, I don't know, like 16 decibels or something like that. Of course not all the energy will translate in tow. Sound pressure. But, uh, let me take the sixth order. Banned best You see it? This one is way louder than the base reflects the normal basements. But this one is louder still in the like we saw it. Um uh, it scored poorly compared to the sixth order because the hole in the bench was obstruct. But let's and take this for now. And let's move on to passive radiator. And the passive re leader is very interesting because it scored the almost the same as the normal based reflects. But the amount of volume in this enclosure is ridiculous. And that is why I specifically chose this lower volume. Because this is a good reason why you will choose a passive radio. So let's look at the frequency response and compare it to the normal base, reflects and see the somewhat match. Of course, it's not that linear, and it doesn't extend that will into the lower octaves, but you can see from these results why manufacturers would show build portable speakers which have limited volume, choose passive braider design because they increase their base output without making the enclosure bigger. Now let's move on to Ban Pass and the 44 other band. Bess is ah, as expected, with a better result than the base reflects. I'm comparing it. The base reflects because it supported design and the and the volume. It's also lower, so the linear based reflects the enclosure. It's almost double in size, so we know that the forefather band best will perform better at least in sound pressure or how low it goes. Uh, compared bass reflex. So if you look at the frequency response church, that man take the passive radiator so we can see the band pass. Um, in this case, it should have played roughly the same as the as the base reflects. But since it's not tuned properly, we couldn't retune it since we use the rectangular port, but normally it will be on par with the base reflects, so it will play justus loud. But the volume is the volume of the box is considerably lower, and it will not extend like we can see, the base reflects goes, uh, easily towards 20 hertz and the band pass wouldn't. Now let's go to the last one, the sixth order band pass, and we can clearly see that this is ah ah, The curve is on the higher magnitude compared to the other curves. And, uh, this result shows as it's the enclosure with the highest amount off SPL. Even though it's a large enclosure on, you will expect to have a large enclosure when you build 1/6 order band pass. But the responses and nearly perfect it goes all the way down to black 24 hertz and up to like, 70 somebody. Something hurts, and it's perfectly linear. It has very good efficiency like we saw. So, um yeah, six. Order Banpais. He's, uh, a nice speak if you can tune it correctly. So this seems like these are the results for our enclosures, which we build. So now you know when you choose a particular design, what characteristics are after so you can choose the proper design for your particular project.