3.4.1: Sound Recording

Exploring the Art of Sound Design

Before we get to how that soundscape is shaped in the post-production process, let’s look at how (and what) sound is recorded during production. The production sound department is made up of several specialists dedicated to recording clean sound on set as the camera rolls. They include the on-set location sound recordist or location sound mixer, who oversees the recording of on-set sound and mixes the various sources in real-time during production; boom operators, who hold microphones on long poles to pick up dialogue as close to actors as possible without being seen on camera (it helps if they are very tall and relatively strong, those poles get heavy after a while), and assistant sound technicians, responsible for organizing the equipment and generally assisting the sound mixer.

And just like the camera department, the sound department has its own set of specialized equipment to make their work possible. Obviously, there are microphones involved. But sound recordists can be as particular about their microphones, what brand, type, and technology as cinematographers are about their cameras. Microphones can be omnidirectional or directional, cardioid or super-cardioid, mono or stereo, and each one will pick up sounds in a distinctly different way. You can use a shotgun mic on a boom pole to target a sound source from a reasonable distance with a shielded cable. Or you can use a tiny Lavalier mic taped to the collar of an actor that sends an audio signal wirelessly to the recorder. Or you can use all of the above in an endless number of configurations, all feeding into the same field mixer for the recordist to monitor and record.

Now you may be wondering, isn’t there a microphone right there on the camera? Why not just use that and save all that headache?

First of all, if you asked that out loud, every sound recordist in the universe just collectively screamed in agony. Second, they’re all so upset because cameras are designed to record an image, not sound. And while they may have a relatively cheap omnidirectional microphone built-in or even inputs for higher-quality microphones, nothing can replace the trained ears of a location sound mixer precisely controlling the various streams of audio into equipment designed to do just that. This is why, even now, most cinema uses dual-system recording, that is, recording sound separate from the image during production.

Dual-system recording allows for more precise control over the location sound, but it also comes with its own problem: synchronization. If the sound is recorded separately from the image, how do you sync them up when you’re ready to edit? Glad you asked. Ever seen one of these:

The Slate.

We have lots of names for it: clapper, sticks, sound marker, but the most common is slate, based on the fact that in the early days, it was made out of slate, the same stuff they used to make chalkboards. It serves two purposes. The first is to visually mark the beginning of each take with the key details of the production as well as the scene, shot, and take number. This comes in handy for the editor as they are combing through all of the footage in post-production. The second is to set a mark for sound synchronization. A crew member, usually the second camera assistant, holds the slate in front of the camera and near a microphone and verbally counts off the scene, shoots and takes a number, and then SLAPS the slate closed. In post-production, the editors, usually an assistant editor (cause, let’s face it, this is tedious work), can line up the exact frame where the slate closes with the exact moment the SLAP is recorded on the microphone. After that, the rest of the shot is synchronized.

In fact, this whole process, repeated for every take during production, is a kind of call-and-response ritual:

1st Assistant Director: “Quiet on the set! Roll sound!”

Sound mixer: “Sound speed!”

1st AD: “Roll camera!”

Cinematographer: “Rolling!”

2nd Assistant Camera: “Scene 1 Apple Take 1” SLAP!

Cinematographer: “Hold for focus. Camera set!”

Director: “And… ACTION!”

Every. Single. Time. And note that the 2nd AC mentions scene number 1, the shot, Apple (for shot “A” of scene 1), and take number 1.

But wait… sound speed? That’s another of those little anachronisms of cinema. For much of cinema sound history, the sound was recorded onto magnetic tape on a clunky reel-to-reel recorder. It would take a moment for the recorder to get up to “speed” once the recordist hit record, so everyone would have to wait until they called out “sound speed!” We use digital recording these days with no lag time at all, but the ritual never changed.

Sometimes, 2nd ACs can have a lot of fun with this little ritual. Check out Geraldine Brezca’s spin on the tradition throughout Quentin Tarantino’s Inglorious Basterds (2009):

Now that we have a sense of how things get recorded on set during production, we should probably cover what gets recorded. The answer: not much. Or at least a lot less than you might think. In fact, the focus of on-set recording is really just clean dialogue. That’s it. Everything else, background sounds, birds chirping, music on a radio, and even footsteps, are almost always recorded after production. The main job of location sound recordists is to isolate dialogue and shut out every other sound.

Why? Because sound editors, the folks who take over from the recordists during post-production, want to control everything. Remember how nothing is on screen by accident? The same goes for sound. Clean dialogue has to match the performance we see on screen, but everything else can be shaped to serve the story by layering in one sound at a time.

There is one exception. Another little ritual everyone gets used to on a set. At the end of a scene, when all of the shots are done, the location sound recordist will whisper to the 1st AD, and the 1st AD will call out: “Hold for room tone!” And then everyone stops in their tracks and holds still, remaining completely silent for at least 60 seconds.

It’s awkward:

But what is room tone? Every space, interior or exterior, has its own unique, underlying ambient sound. What we sometimes call a sound floor. During production, as the actors deliver their lines, the microphones pick up this sound floor along with the dialogue. But in post-production, as the editors pick and choose the takes they want to use, there will inevitably be gaps in the audio, moments of dead air. Room tone recordings can be used to fill in those gaps and match the sound floor of the recorded dialogue.

Of course, as I mentioned, it can be a bit awkward. But it can also be kind of beautiful in its own way:

Room tone is just another example of how sound editors control every aspect of the sound in the cinematic experience.