You may have found yourself in this situation before: you are editing a dialogue sequence, and you need to add a little bit of a pause that the actors didn’t put in there when you shot the scene. You add it, play it back, and there is something very noticeable when you encounter that pause in the timeline – the lack of dialogue is not the thing that sticks out – it is the lack of the tone of the room that produces an ugly audio gap.

What happened? Well, inside of that gap is complete silence. Absolute digital silence. But wherever you are reading this right now, close your eyes and listen to the room your in. No room is absolute silence, and the quiet subtleties you are hearing in your room are known as room tone. It’s important to know how to use room tone to avoid audio editing difficulties.

Ideally, for shooting dialogue and other similar scenes, your shooting room should be very quiet – free of air conditioners and helicopters outside. But even the quietest room has a different sound to it, a different tone. This could be affected by a lot of things. For example, what is on the walls? Bare walls along with no furniture and tile floors bounces sound around and you get a more echo-y, hollow sound. A lot of soft furniture with things on the walls (especially something like a hanging wall carpet) absorbs sound, and you get a warmer sound.

The point is, each room is different, and a smart thing to do for your production is to recognize this and use it to your advantage.

Getting Room Tone

The easiest way to get room tone is to make a habit of adding in one more step before wrapping a room during shooting. Before everyone packs up for the next setup, tell everyone to “hold for 30 seconds of room tone”.

Everyone should get quiet, and whoever is recording audio (it could be you), should identify the room tone take into the microphone, and point it horizontally for 30 seconds. If someone coughs or falls down, start again.

When you get back to your editing program, and you have a folder with your scene files, you should now have one you’ve named “Room Tone”. You may use it, you may not, but it’s the mark of a good production to always have it handy for each location.

Room Tone vs Ambient Noise

Remember that room tone is different than ambient noise. If you are shooting at an amusement park and want the sounds of the crowd having fun, that’s ambient noise. It’s too busy and varied to be room tone. We’ll talk a little bit more about ambient noise later this week.