Noise Floor of Studio/Vocal Booth


Recently I installed an extraction unit in a vocal booth. I ran this through a silencing system which works brilliantly and then added a speed controller. The result is the quietiest of 'ssssshhhhh's in the booth. Barely audible but I was concerned that it could be picked up on the mic.

The software I use is Reaper and it does not register on there. The interface software is Audient and right at the bottom of the scale peeps a little bit of sound registration, mainly between -55 to -60.

Turning the playback volume up in my phones I can tell what each sound is. The loudest is the extraction fan. Then I have the pc fan which is outside the booth. The rest is distant exterior noise which cannot be heard any other way. This noise is vehicles.

I know I could actually reduced this by turning the mic gain down, but it will still be there.

So my question is ........ What should the 'noise floor' of a vocal booth be?

rob aylestone

Well-known member
As Rolls Royce say when asked about power characteristics of their engines - 'sufficient'.

Perfect is silent. You had to turn everything up to hear the noise, that's not how it works. Audiobook recordings are the most exposed, but silence is never possible because of script noise, breathing, leather chair noises and clothes. If you had an anechoic chamber, the person would still make noises. Chasing silence is VERY expensive. There is as far as I am aware, no figure for what silence (as in practical silence) is - there is a famous isolated take of Robbie Williams singing where you ca hear him fart - you don't hear it on the finished track, but it's there. You use reaper and nothing registers on it's meters? Great - job done. When I plug a mic in, there is always some activity right at the bottom - but the only question that matters is can your ears hear it at the normal working volume. When I record dialogue, the phrase "can we stop there" is used lots, but it is the noises I hear that trigger it. the background noise is low enough that the chair creak triggers a stop, and that is a quiet noise. The purr from the extraction system is low enough. I record quite a bit with mics, and could hear the computer, so in the re-design last year, the computers are now in a separate space, with a fire door between them and me, and I can't hear them now.


Thanks for that Rob and the recordings are for audiobooks/stories of which many have been recorded but not edited yet. Hence the disheartened question. But I feel ok now after your reply. Cheers. (y)