If you've been on a set, even an indie project, you've probably had to suffer through an awkward few moments of silence when your production sound mixer asked everyone to hold for room tone.
But if you've never been on set, you might not even know what this means or why a recordist needs it.
And you definitely need it.
Let's go over what this important filmmaking term is and how to record it like a pro.
What Is Room Tone in Filmmaking?
Every space has a sound, even when it seems to be completely silent. We don't usually exist in a void or big sound-proof bubble. There is traffic outside, or the buzz of your AC, or static from a radio somewhere, or the hum of an elevator somewhere else in the building.
The ambient noise of "silence" is what filmmakers call room tone.
You need it for several reasons, realism included.
It might seem counterintuitive to record silence, but this recording becomes important during post.
Each location has its own unique sound. Imagine you're in a big echoing gymnasium. Now transport yourself into a small closet filled with winter coats. They're going to sound different, even if you're just standing there by yourself. Each location is going to sound different based on where you're standing within it, too.
Room tone or ambient sound is going to differ based on the microphone's position, too. This is why sound recordists typically capture fresh room tone for each new camera setup and location throughout a shoot.
Who Captures Room Tone?
The person responsible for capturing room tone is usually a production sound mixer or location sound recordist on set.
Better Call SaulCredit: AMC
What Is Room Tone Used For?
During editing, dialogue tracks almost always need patching. Someone coughed during a take or bumped a prop. A helicopter buzzed past, maybe.
As an editor is splicing together the best version of the dialogue, there might be some empty spaces. Without room tone, these fixes would create dead air. The soundtrack "going dead" sounds really weird when you don't have room tone to fill it. You might have heard it in an ultra-low budget production and you probably noticed it as a mistake.
If you need to add ADR (dialogue recorded later in a studio, not on set), that clean audio will sound much different from the on-set recordings unless you layer room tone underneath it.
Sound editors also use room tone to create natural pauses in dialogue and smooth transitions between takes.
How to Record Room Tone
Recording room tone is straightforward. You just have to remember to do it.
“It’s almost one of the most awkward and hardest things when you’re on set to do,” director Michael Gabriele told Screen Magazine.
At the beginning or end of your shoot, when you've set up your microphones and equipment, ask everyone on set to remain completely still and silent.
Position your microphones where they'll be during dialogue recording. For spaces with steady background noise (a drone, a buzz) grab 30 to 60 seconds. When the ambient sound shifts and changes, record longer. Say you have traffic or a train outside. Maybe record a few minutes, if you can get away with it.
You don't want to break the set down, then come back when everyone's gone. It will sound different with fewer bodies in the room.
The most common mistake filmmakers make is simply skipping this step because everyone wants to wrap and go home. But those thirty seconds of recorded silence will save hours of frustration in post-production.
For more tips on improving your production audio, check out our guide to recording production sound and our breakdown of sound recording basics.
You'll also want to familiarize yourself with proper audio levels when recording to ensure your room tone (and all your audio) is captured at the right quality.
