An Introduction to Post-production Sound for Film

1. Welcome!: Sound not only adds to film but it's an essential part of the narrative As a sound designer, being able to create sound for Film is really rewarding, but if you're a director or a video editor having a basic understanding of how sound works, in particular post-production will help take your project to the next level Hello everyone! I'm Gabby and, welcome to "An Introduction to Audio Post-production" in this class we will cover all the basic aspects of audio post that you need to know in order to get the best results for your work. Audio post-production is where all the elements of sound come together, and you might have seen our previous courses on pre-production and production sound and, in this class we bring all that knowledge and the results from those stages together, to create a final polished piece of film. The key components to audio post and the areas that we're going to cover the basics on in this class are: dialogue syncing and editing, ADR, sound effects editing and sound design, foley, music editing and mixing. Film post-production is one of the longest phases of producing a film, there are a lot of elements that need to come together, at different stages throughout the post-production process, in order to deliver a final cut ready for distribution. Throughout this class, I will demonstrate the techniques discussed and give you examples before and after each step and, for the sake of this class, all my demonstrations will take place within Pro Tools as this is industry standard but, if you use a different program or piece of software, what I show you in Pro Tools is completely transferable to the software you are using as long as the features are available. Also it's worth to mention that there is a free version of Pro tools you can also use if you need to. For the class project, you will get to unlock your creative self by working on a short scene where you'll be able to practice all the techniques learned in this course, from dialogue editing to sound effect design. Everything that you need can be found in the class materials. Whether you're a filmmaker, new to this or a filmmaker that's been working on films for a long time but have never stepped inside the world of audio post-production, this class will help you step up your creative knowledge. I'm so happy that you've joined this class. Now, let's get started and thank you for watching. 2. Picture Lock and Spotting Sessions: In order to begin the audio post-production for a film, picture lock needs to be completed. This is so that you can work off a piece of footage that will not undergo any changes. This is because if, visual changes are made, i.e cutting scenes, then all previously synced audio will no longer be in the right position on the timeline. And in many cases, fixing this goes beyond just moving all the audio on the timeline. Shaving frames here and there might mean a full modification of sound effects, foley and more. Once you have your locked film, it's time to start the spotting sessions. A spotting session involves a director and the sound design team. And during these sessions they will discuss the sonic elements of the film by watching the film and, marking points for recording, editing, and creation. This is a crucial part of the process as it allows a clear communication of the director's vision to the sound team. Things that should be discussed with the director are: general tone and aesthetic, world building so, what is the world like with the characters are living in? What's the timeframe, things like that. Any specific moments for sound design and flagging up any problematic areas such as bad production sound or dialogue. I've added a template for the spotting sheet to the class materials. So, feel free to use this for the class or for any of the words that you might do, too. 3. Sound Sync: Before picture lock and just after the production sound team has delivered audio to the film editor, sound sync usually occurs. Sounds sync is usually performed by the film editor. However, if your project is a one-person show then you might find yourself doing this on your own. During the film, the sound and photography crew must have ensured that they were both capturing audio and video at the same frame rate and, agreed on a synching system. A clapperboard is a must and having this reference both for picture plus the traditional clap, will allow editors to synchronize audio to video without a problem, regardless of any other implemented syncing system and any problematics that might arise from their use. Using technologies which enable video and audio devices to sync includes synchronization by a jam sync, which uses SMPTE time-code in which a master device informs time to a device which depends on it. This can be done in a variety of ways, such as using a device like the tentacle, which communicates with the camera and audio recording device via Bluetooth or via connecting a BNC cable just to mention a few. All of these work great, but they can also bring unexpected issues so, always having a low tech clapperboard is key. Once the film editor has all the footage, they will use the video editing software of choice. Software like Premiere, will allow you to merge video and audio clips by identifying the waveform created by the clapper board. And there are some other smart features now, that sync based on time-code. Whichever the way, if you're an editor, arriving into a project shortly after the production has commenced, or even a little bit later on, make sure that you ask for all the notes. done by the sound crew and the script supervisor. 4. How to Edit and Clean Dialogue: Once you've been through the spotting sessions with the team, or by yourself if you are directing and working on the post-production on your own, it's time to move on to the dialogue editing. During the picture lock stage, the editor should have synced all the production dialogue along with their video edits. This includes ideally not only one source like the shotgun mic, but also any other sources captured like the radio or room mics. At this point, the dialogue editor can select which production dialogue tracks, work or sound the best for the scene and begin cleaning and editing these as needed. Having said that, it is not uncommon for the film editor and director to make choices of audio takes. This is also a good way to work however it is always best practice to put these takes at the top of the session and keeping the other synced audio at the bottom. If your team is big enough that you are working with the five elements audio separately, then a session with only dialogue organised in the manner I just explained is given to the dialogue editor with no sound effects, ambience or music tracks required. However, if only one person is working on the audio for your film, then colour coding these dialogue tracks is advised. Once you have checked the sync or done the sync of the dialogue for yourself, you need to ensure that any unwanted noise is removed from tracks and that they are trimmed down to the required length. With dialogue cleaning, we'll begin with what could be described as a low tech solution. Rather than getting overly excited and jumping to the use of plugins and other auxiliary tools like EQs and compressors right away. We first need to clear the way by cutting unwanted and unnecessary bits of audio. And performing volume automation. Always taking care that there are no dramatic audio dips, cuts that make the dialogue sound overly artificial. An example of this is this bit right here. Here the solution is quite simple. A cut of this bit at the end of the audio and a very short fade out does the trick. Another very important and basic concept is that of replacing gaps with room tone. Throughout our other courses on pre-production and production audio. We've told you about room tone and the importance of capturing as much as possible when filming. Dialogue editing is not the only reason, but it's probably one of the most important reasons why we do this. Take for example, this section here. We will need to remove this noise. However, if we just cut it out and even adding a fade out at the end of the audio clip and a fade in at the beginning. The silence is really noticeable and makes the audio sound artificial. Fortunately, because we have room tone at our disposal, we can fix this. Remember, dialogue needs to be clear and intelligible. If you have found during the spotting phase that this is not the case for some of the production dialogue. You may need to think about doing ADR, which is automated or Additional Dialogue Replacement. If there are some noises in the background of the dialogue, recording it may be possible to remove these. A good sound mixer will ensure a recording is taken of any noise pollutants that could not be avoided during the filming phase, for example, and a noisy portable battery that's used to power the lights or the humming of a refrigeration unit. Capturing a recording of these sounds on their own can allow audio editors to filter out these sounds in post by using plugins such as Izotope's, spectral de-noise. we solved This is another very important use of room tones we solved With all your dialogue nicely synced and cleaned up. You can now move onto ADR if that is a step that is required for your project. 5. How to set up an ADR session: Quite often you'll find that some of the audio recorded onset is either too noisy, corrupted, missing, or just not the quality needed and ADR is the way to resolve these issues. ADR is the process of recording new dialogue in a studio environment to sync with the video. It will require the actor to lip-sync to the original performance as closely as possible. The actor should make sure to try and deliver the same emotion and power that they expressed during the original recording. Broadly speaking an ADR session is comprised of a screen relay and a microphone of choice for the actor to perform with. The ADR recordist will prepare a session with the picture and sync any audio as reference for the actor, as well as set up a room for the actor to perform in. Which is usually void of any electronic noise that's coming from the audio equipment. Once you have this, the actor can decide whether they wish to perform hearing their reference audio, or if they prefer to do it in silence, only watching the screen as a cue. Particularly for smaller budget projects, it is common to have the director attending these sessions to make sure that the actor can be guided or coached, in an attempt to deliver something as close to the original performance as possible. To prepare your audio recording session, consider the same aspects that we discussed on the dialogue editing module. You must deliver only our dialogue tracks with the selected takes at the top and the rest of them below. And while you might be informed about aspects such as bit depth and sample rate by the production sound. Do bear in mind that the minimum requirements should be 24-bit and 48 kHz. These days sound recordists and sound designers do tend to use 96 kilohertz as almost a standard, as this allows for better processing of the recordings without artefact noises and so on. While setting up an ADR session and running it could be a class on its own. I will just brush upon a couple of the aspects that should be taken into consideration. The most important is having a queuing system. Nowadays there are software such as EdiPrompt or the Colin Broad system. In either case, you can choose between using audio beeps to queue your actors before the scene plays, or you can use visual wipes to do the same. Going really low tech, you could program these queues manually, but this could be extremely time-consuming, particularly for a film that requires a lot, of ADR. Whatever your choice, the important thing to remember is that you need to have a system in place so your actors can know when the action is happening. Other aspects to bear in mind is monitoring. As I mentioned before the actors will usually be in a recording room with a recordist in a control room. So it's necessary to create a monitoring mix for the actors to be able to hear themselves, as well as any feedback from the control room and if needed, any aspects from the recorded audio of the film that they wish to hear, like a previous performance or specific sound effects or ambient sounds. We will be releasing an ADR focused class in which we will go over each step of setup in detail. 6. The Basics of Sound Design: Sound design is the process of creating audio effects for picture. Sound designers will add wild tracks and field recordings to create ambience for each scene. And along with that, they will add any specific or special sound effects that are needed. Sound effects can be created in a number of ways. It's usually a mixture of recorded sound which are layered up and sometimes have light to heavy processing applied, depending on the sound effect and the genre of the film. It is a sound designer's job to bring the scene to life through sound. And sound has a huge part in telling the story, and a great sound designer can add much more to the story than what the image can convey on its own. Sound design can be as simple or as detailed and elaborate as you want, but it needs to make sense for the type of film. In this class, we will go through basic sound design, which is generally the foundation for nearly all films that are produced. That is because to some level, all films consists of the same types of sounds in my own experience and from what I've heard and seen from other sound designers. The key to creating great sound design is collecting and using nice organic materials, so sounds, which on their own may not sound like anything special, but once layered up together, create a dynamic and sonically interesting moment for the listener. Likewise, a correct understanding and use of silence is also required. Take for instance, this sound here. These are the layers that are involved. Next time you're watching your favourite film. Listen, particularly those scenes which are the most compelling. What is happening sound-wise? How is the film using layers or even silence to convey motion or lack thereof? Now think about how you can apply this to your work. 7. What is Foley and why do we need it?: Foley is similar to sound design as it is the process of creating sound effects to enhance the picture and make it seem more realistic to the audience . Foley however refers to human-made sound effects such as footsteps, clothing movement, and prop handling by the characters on screen. The Foley artists will perform actions along with the footage. And in a similar way to ADR, it needs to be in sync and match the performance given on screen. It can then be edited to make sure that the sound matches the scene, not only in terms of sync, but in terms of space intention and more. A lot of Foley sounds are relatively straightforward and a foley artists can simply use similar objects to what is being used by the actor. But for some sounds a Foley artists needs to get creative with the materials that they have around them. As in a lot of cases, the actual object, may not actually sound like how you would expect it to. Just how a sound designer will layer up multiple recordings to get the sound they need. A Foley artists may hold multiple objects at the same time and move them around to get the desired sound effect. From the world of foley we get a lot of the most well-known tricks in cinematographic sound, such as coconut shells for the sound of running horses, boiling bacon for rain. And many other fun, yet super useful tricks to think about that Foley artists have developed over the years and that our ears as spectators have just grown accustomed to. You might be wondering if the sound recordist and the boom operator did a good job during the filming phase, then why do we need to foley in the first place? Well, the reality is that during the filming phase the sound recordist will try to capture all the sound to the best of their ability. But priority will always be given to dialogue. If you've seen our classes on production and pre-production sound, you will know that there are many different elements that might affect audio during filming, including noises from several sources that can't be controlled like traffic, passer buys electronic noises, just to mention a few. So recording techniques and microphone placement will always be focused on trying to capture clean and crisp dialogue. Meaning that for those noisy environments, capturing footsteps, clothing, movements, and so on, it's just not a priority, but it's ill-advised to be honest. For this reason, if a sound recordist did a good job, what you will often hear is very clear dialogue with little to no other sources of sound on it. In terms of budget, creating foley is a very standard part of postproduction. And it means that costs are not significantly elevated as opposed to having to do ADR, for instance. Also bear in mind that creating and foley in post-production can actually be an advantage as it allows for sound designers to control the circumstances under which these foley sounds are recorded, allowing for a clean sound that can then be transformed in any way desired for the film purposes. 8. Music Editing: Music is a very important element of the narrative. When composed and used correctly, it can add to the visceral elements of a film. Music editing is crucial, and it is a role that acts as a bridge between the sound team, the music composer and picture. A music editor will help the director achieve their musical vision for the film. And depending on the size of the project, the music editor will work closely with the composer, director and even the editor to achieve a consistent rhythm that aligns video and music to the same pace. Some of the main responsibilities of a music editor early on is to create a cue sheet for the musicians or composer to follow when performing the music so that it matches the editing rhythm. Additionally, choosing and understanding where the music comes in and out of a particular scene are decisions that a music editor can help make. This also extends to utilising silence in a smart way and when there is music that is sourced in a royalty free basis, the music editor can help decide what are the best pieces of music to suit each scene and important narrative moments. In bigger projects, the music editor will then work with the music supervisor to ultimately accomplish this task. Editing music is a complex and beautiful process, which involves not only knowledge of rhythm, but also of musical composition and style. Creative cuts and edits to compress relevant musical themes, as well as to bring in phrases of music together that are not normally in sequence in a seamless manner, all require this previous knowledge. Look at the class resources to see an example of music editing and the positive impact on film. 9. Dialogue Treatment: We have discussed cleaning and syncing dialogue before, but is there anything else that we can do with it? The answer is yes. The work of a dialogue editor goes beyond making sure that any silence gaps are filled and that the dialogue is always intelligible. As human beings, our ears are designed to recognise a subtleties in other human beings voices. We can recognise intention, emotion, and even in certain situations, overall health levels and medical conditions based solely on the voice. When working with dialogue, there is a lot of creative elements to bear in mind. Who are the actors speaking on stage and what are their motivations? In a recent film that my team and I had a chance to work with. We had a character whose qualities were charming, smart, reassuring. And this was despite the fact that development of their storyline ended up showing the audiences that the character wasn't so good after all. As such, it was important to make sure that the voice of this character was appealing and pleasing to the characters ears. To do this, we made sure that a special EQ mix was created for this character's voice and one for each source. So in this case, a shotgun mic and a lavalier microphone. The EQ mix helped reduce some of the more shrill like frequencies on the actor's voice. While subtly increasing the mid, mid to high frequency bands to give the voice a warm, honey like texture. A couple of preset options of reverb and compression were also created for this character to make sure the voice was always soft yet present. On the other hand, a different character needed to make the audience feel uncomfortable. And the characteristics were more nagging, petulant, and poignant as such, almost an opposite approach was taken using compression and equalisation to make sure that there was a slight boost on those frequency bands that our nasal cavities resonate with when voices are more high-pitched and shrill. All of this had to be done in a subtle way, yet big enough the effect was felt but the audio wasn't distorted or modified in a way that made it sound like these characters were both in different places. This is just an example out of many on what can be done in dialogue to convey more about the characters. If doing ADR, you must also take this into consideration so that when you record, you should choose the right microphone and equipment help you with this process. 10. Ambient Sounds: Before getting deep into mixing, I want to talk a little bit about ambient sounds. Foley, sound effects, and music receive quite a lot of attention when it comes to sound design. And for a long time, and particularly in the early stages of film and also with the rise of television. Ambient sounds were seen as fillers or portions of audio that could be used to get a bed to the rest of the sounds and dialogue, as a way to trick the ear into hearing everything in context. However, when talking about film, ambiences can push the narrative forward as much as any other sound element. Because ambient sound is something that our ears are used to interacting with or sometimes even neglect in favour of spoken sounds. And opportunity is presented to use ambiences to introduce a less obvious element to the narrative. Soft changes in room tone, introduction of specific elements in space like leaves rustling or dogs barking, crickets, or any other environmental aspect can tell us where we are. And cue us subconsciously as to what is about to happen next. Natural phenomena expressed through ambient sounds such as rain, running water, cold or hot wind. can make us empathise with the characters on screen and set the mood for a change in emotional content. On the other hand, ambient sound can also be used in a much more forward manner. Ambiences created with soft droons, rumbles and even changes in wind can help overtly tell audiences something bad is about to happen. More artistic atmospherics are a huge part of what is done horror films for example. An important thing to remember when working with ambiences is that similar to a sound effect design, setting up an ambient for a scene might require many layers of recordings to achieve the desired effect. In real life, our ears are constantly receiving many layers of complex sound information. And our brains make the work or prioritising different layers depending on our state of mind and emotional contexts. When working with ambiences, we're adding these layers and we're doing the exciting task of choosing what we should prioritise for the audiences, adding meaning and even getting into the character's psychology by doing this. 11. Mixing: One of the last stages in post-production is mixing. At this point, all the other components that we discussed are brought together and combined by the dubbing mixer or re-recording mixer. During this stage, the audio is balanced to create final audio mix. This requires levelling on every single sound from all sources, effects, foley, dialogue, music and ambiences need to be blended seamlessly. It is an arduous and long process, that requires the extensive use of automation and other tools such as EQ and compression to make sure that all the relevant sounds can be audible, rather than a mash of noise from which no specifics can be set apart. Alongside levelling decisions on usage of silence, as we discussed previously, are also done. The director will be involved in several sessions with the sound mixer to make sure that the overall vision is achieved. The sound mixer is also responsible for adjustments such as positioning and loudness levels. This last aspect is perhaps one of the most technical ones to bear in mind when mixing. Sound for the purposes of film and any audio visual material that is presented in any medium be it cinemas, television, or streaming platforms needs to be measured in loudness levels. Several standards have been developed and should be followed according to the platform in which the film will be played and your geographical location. The truth is, we could dedicate a whole class to loudness standards and the preparation of mixes for their reproduction in different mediums. And we will have a course focused on this area in the future. But for now, I will focus on two standards used for film projection in cinema. The EBU R 128, the ATSC. Before I do that, I think it's important to talk about loudness and how it is different to volume. Volume, which is a concept that we use in different contexts and very often is simply put, the scientific measurement of power in sound. We talk about volume when we regulate the level at which the sound is played on our computers or televisions, we can increase the volume and as a result, we hear the sound come in as louder. Loudness, however, is a very different thing. It refers to our subjective perception of sound and is a much more complex thing to measure. This is because not only the amplitude and power of the sound is measured, but also the frequency, composition and duration. For example, the way we perceive how loud a high pitch sound is versus a low pitch sound is very different. And bear this in mind. That is only one sound, add the thousands of sounds together that you'll be hearing on a film. And it becomes a whole different ordeal. Standards to measure loudness in cinema projection rooms have already been developed and tested. The same applies for standards for online streaming platforms, media players on computers and television. Which takes us back to the EBU, R 128 and the ATSC. Both of these are loudness standards which ensure that sound mixers follow a protocol so that all films that are published in cinema have the same perceived volume throughout. The EBU R 128 is the European standard. While the ATSC, which stands for Advanced Television Systems Committee, is more commonly used in America. Their loudness levels are measured in LA UFS or LLF KS. which stands for a loudness unit, only vary by one or two points. Admittedly, a couple of points louder in Europe than it is in America and this has to do with the average construction of the cinema rooms and projection equipment and much more complex aspects which we won't get into in this introductory class. It is sufficient to know that the industry standard loudness plugins come integrated with these measurements already in. For example, insight, which is a Mastering plug-in from a company called Izotope, that message levels in your project according to the standard of your choice. Izotope is not the only company that produces these kinds of measuring tools. We have Waves, Nugen Audio and many, many others. A film should have an average program level of around -27 LF KS with a true peak of -1 dB maximum. Both these measurements will be shown in your plug-in, so exercise caution with your film if it's over or under these levels and adjust if necessary. Ear and experience also come in handy as adjustments required by the standards will need the sound mixer to make use of their ears so as not to lose the desired effect when it's just in the overall levels. Once the film is mixed. The next part depends on your distribution platform. If your film will be showcased in commercial cinemas, then it is very much likely that your film will go through encoding and the creation of a digital cinema package will be required. Look at our course resources to learn more about the specifics on a digital cinema package, which might need to be created if you are sending your film to say, international film festivals. For a larger budget film, your film alongside the synced mix can be sent to a digital cinema encoding facility to create a DCDM or digital cinema distribution master. But this is a more advanced topic which we will go into more detail on future courses. 12. Final Thoughts: We've come to the conclusion of this class. Congratulations and thank you for taking this journey with me. I hope that what we've covered here has given you an overview of how crucial post-production sound is to the success of any film. But also that you've found the concepts here and the craft as interesting and as beautiful as I do. We have covered basic concepts on sound synchronization, how to clean and treat dialogue, as well as how foley and sound effect design work. We have also learned about mixing and the preparation of a film for sound and its distribution. In the future, we will be releasing new classes with much more advanced concepts on audio post-production. And we will go into even more depth about specific editing and sound design techniques that can be used when working on a variety of genres of film. In our course exercises and resources, you will find the materials to complete your class project, which we'll see you cleaning, editing, and performing basic levelling on a scene from the documentary 'Finding Sid'. Additionally, you will find a couple more of optional exercises to practice sound effect and ambient layering. Please share the results with the rest of the class. Good luck, and I'll see you again very soon.