Audio Post Production Glossary | 10 Top Terms Every Engineer Needs to Know

The world of audio post-production is exciting and constantly evolving. It requires engineers working in this field to be up to date with the latest technology and techniques and also to clearly and accurately communicate and collaborate with other professionals. Having to talk with directors, video editors or film producers we need to make sure that we understand their needs and requirements by sharing the same vocabulary.

That is why one of the key tools an effective audio post-production engineer needs to be able to draw on is the terminology and argot employed in the industry. If you’re moving into film and tv from music recording this can be very different to what you already know. Terms like: ADR, reconforming, wild track or picture lock are part of everyday conversations. 

In this article, we are going to cover 10 of the most common concepts and vocabulary that a 21st-century engineer, working in the field of motion picture, needs to be fluent in. It’s not an exhaustive list but it will get you started! Here are the top ten terms that make up our audio post-production glossary.

Location Recordist

Recognizable for wearing headsets, a bulky bag on the front and a fluffy microphone mounted on a boom, the location recordist is the member of a production crew responsible for recording all sounds on set during filming. They will be responsible for recording the dialogue, room tones and ambients on the location. This recording will be used in the finished product, or for reference by the sound designer, sound effects editors, or foley artists. 

The location recordist needs to know the script and work closely with the actors to capture the performance correctly, avoiding any noise happening on set. They are also responsible for making sure that the video and the audio keep in sync by using the same timecode. This leads us to our next term…


Timecode is a sequence of numbers generated by a timing synchronization system. This is a clock that ticks in frames, rather than just in seconds and keeps track of when the video and audio are recorded. It’s stored as metadata within the files and it’s used for temporal coordination and reference by the edit and sound departments of the production,

At the beginning of a shoot, the timecode is synchronized between video and audio devices giving everyone the same reference. There are different timecodes in the industry but the SMPTE (Society of Motion Picture and Television Engineers) family of timecodes are almost universally used in film, video and audio production.

Wild Track  

We call Wild Track to any audio intended to be synchronized with film or video but recorded separately. Whether it is some extra dialogue, sound effects, or ambient noise gathered without cameras rolling, the wild track is there to enhance the picture. An example of this is the voice of Venom in the homonymous movie. During filming, Tom Hardy recorded his lines as Venom right before shooting the scene, to act against “himself” during the actual shooting. You can watch Will File, Sound Designer and Mixer, explaining it in How to Create The Sound Of Venom.


Also known as atmosphere or background, it is part of the wild track of a movie. It consists of the sounds of a specific space. Every location has a distinctive sound created by its environment. This can include birds, wind, music, rain, the sound of people moving or even the noise from an aircon unit. Ambience is normally recorded during the production and it is used to provide sonic space for each scene.


One of the first processes that need to be finished before the audio post-production team gets to start with the project, is video editing. The video editor will go through the Edit Decision List (EDL) of the picture and come up with a final edit of the movie. This is what we call picture-lock. However, as we will see, these final edits can be not that final after all. More on that later.

Automated Dialogue Replacement or ‘ADR’

ADR stands for Automated Dialogue Replacement. It refers to the process of re-recording an actor’s dialogue in a studio environment. During an ADR session, the actor watches and performs a scene of themselves in order to dub a cleaner dialogue. Whether the original recording was too noisy, lines of the script were changed after filming or it is just an artistic decision from the director, the process of ADR is ubiquitous in the post-production industry. Some actors have even modified their performances in order to make this process easier. You can watch Walter Scott Murch, ADR supervisor in the Godfather, talking about the ADR process with Marlon Brando. And check out our blog ‘What Does An ADR Mixer Do’ to find out more about this type of work.

Sound Effects 

When most people hear the word sound effects they instantly think about lasers, explosions and spaceships, but in the audio post-production world, sound effects are any sound other than speech or music made artificially for the production. They can vary from screams, footsteps, breathing, typing and of course lightsaber sounds. All of them help create the sound environment that surrounds the characters. Most of the time a simple-sounding element on the screen is composed of several layers of different sounds. The engineers that carry out the work of collecting and placing these sounds in the correct position of the film are called Sound Designers. 

Some sound effects have been used in hundreds of productions and a few have even become a pun or a challenge within the creed of sound designers to add them in every production. The most memorable one is the Wilhelm Scream. It has been around for over 50 years and you have been hearing it in many blockbuster movies, TV shows and video games. Even in Thomas The Tank Engine. Don’t believe me, just watch (or listen).


Can you imagine being in a studio full of metal scraps, water bowls, sandboxes and a whole hardware shop ready to be recorded? That’s what a Foley studio looks like. Within the sound effects world, foley is a technique that involves creating and “performing” everyday sounds tailored to a specific production. The name comes from Jack Foley, the sound effects artist who developed and shaped this technique creating sounds for radio on cue. 

Wind, steps, water, windows breaking…Foley artists are in charge of creating these sounds during post-production. They perform in synchrony with the picture, using elements from their collection, to enhance the audio experience of the movie.


As we mentioned before, the ideal scenario is to have a picture lock before doing all the audio post-production work. However, it is common that the final edit needs to be changed after the audio post-production has already started. In these scenarios, the two video edits need to be compared in order to rearrange all the audio work done. This is what we call reconforming. This process can be hard work and frustrating but thanks to modern technology there is various software that can help to alleviate this load. Matchbox, Conformalizer, Virtual Katy and EdiLoad are some of the tools that are used in order to update an audio post-production project without having to start all over again. Pro Tools Expert has a great and detailed article about how to approach Conforming and Re-Conforming when the picture-lock has changed.

Immersive/Spatial Audio

Throughout the years the search for improving the audio experience of the audience has led to several technological changes on how sound is delivered in film. From Mono to Stereo, through Quadraphonic, Dolby Surround to the latest Immersive audio. In the latter, a set of speakers in the walls and ceilings of a room produce a sound that the listener perceives as coming from “all-around”. It provides the audiovisual industry with the ability to create three-dimensional audio spaces to immerse the audience in the story.

One of the technologies that allow the creation of this spatial audio is Dolby Atmos, which had its debut with the movie Brave in 2012 at El Capitan Theater in Los Angeles. But it’s not only limited to big theatres and cinemas. In the last few years, this technology has been brought to listeners headphones using audio processing algorithms. 

In 2017 Abbey Road Studios launched the Abbey Road Spatial Audio Forum which brings together artists, producers, engineers and academics from the world of music, film, broadcast, VR and gaming to share their research and results in spatial audio. The main objective is to find new creative approaches within three-dimensional sound and inspire the creation of new original immersive music. Check out Abbey Road’s Spatial Audio website where you can find plenty of articles and interesting links to feed your curiosity.

This Audio Post Production glossary gives you a flavour of some of the terms and topics that our Advanced Diploma in Audio Post Production for Film and TV Diploma students will be learning and immersing themselves within. If you’re curious to know more about this fascinating field of work read our interview with award-winning Re-recording Mixer and Sound Designer Rob Walker. And head to our course page or get in touch to find out more about studying with us. 

This article was researched and written by alumnus Carlos Bricio.