Learning The Basics: Audio

Post By: Sarah Barclay

Audio is an important part of film, about as equally as the visual aspect (depending on the type of film you’re shooting). Audio includes things like dialogue, sound effects, narration, etc. Here, we’re going to introduce you to and explain the different types of audio most commonly used in filmmaking.

ADR

Automated/Automatic Dialogue Replacement, or ADR as it’s more commonly referred to, is the process in which an actor re-records their dialogue after the filming process. This is usually done to improve audio quality or to reflect changes in dialogue. ADR, like other facets of film, is a part that you only notice if there’s something wrong with it.

The problems that come with ADR is that it can easily get out of sync with the movie and the character it’s attached to. While it’s not something that’s immediately noticeable, as film students, we analyze movies all the time, whether we mean to or not. When ADR is off, we notice it, almost immediately.

Foley

Foley is human made sound effects recorded in studio during post production. We have both an article and video which goes more in depth about foley. You can check out the article here or the video below for more information.

SOT

Sound On Tape or SOT refers to audio recorded on any video format. SOT’s are used more for broadcasting than in filmmaking, but we still feel it’s important to mention. SOT’s can also be referred to as sound bites, which are about 8 to 30 seconds of video featuring a person in a medium shot (see our guide to camera shots here) talking on camera. It’s important to note that when writing a script for broadcast that you must include SOT on any pre-recorded story to prevent confusion of what the anchor says and doesn’t say.

VO or OS

Voice Over (VO) or Off-Screen (OS) is a piece of narration, not part of the image that’s being shown. VO is more commonly used in broadcast while OS is used in film. Voice Over in broadcast is used when the anchor reads something which accompanies the visuals seen on-screen rather than a(n) SOT. This is also specified in the script.

Off-Screen in film is used with characters who don’t physically appear on-screen. This is often used with montages or phone calls, focusing more on the action, a specific character, or concealing someone’s identity from both the audience as well as the other characters. Voice Overs can be vital to a film or they can be a complete distraction, there’s a balance needed, dependent on the nature and subject of the film.

Single System vs Double System

Single System recording is the process of recording audio on the same device used for recording video. With this system, audio and video are automatically synced, but quite a few single systems don’t record the best quality of audio. Their main purpose is to record video.

Double System recording is the process of recording audio on a separate device than the video. This produces a better audio quality, but you have to sync that audio with the video later in post-production.

Movies today use Double System recording, collecting dialogue using a boom microphone. A boom mic is a directional mic (recording audio from one direction) mounted on a large pole held up by a boom operator. The mic itself is plugged into an external recorder which picks up just the audio. The mic is also covered in a fuzzy windscreen called a dead cat (yes, really). The dead cat works to minimize wind noise while remaining acoustically transparent. In other words, the dead cat improves the audio without affecting the quality.