Release on compressors

JJV

I was reading "Mixing Audio - Concepts, Practices & Tools" by Roey Izhaki. Its a great book but I was surprised by his explanation of what the release time on a compressor does.

For years I have been labouring under the misapprehension that the release time determined the amount of time it took for the compressor to stop gain reduction once a signal drops below the threshold.

Apparently not. He says:

"As opposed to what many sources state, the release function is not related to the signal dropping below the threshold."

He goes on to show a noise burst going through a compressor & in the illustrative waveform you can clearly see the attack & the release part of the gain reduction happening above the threshold.

My question is then, what exactly triggers the release on a compressor & have others also been taught incorrectly about this?

Thanks.

JJ (www.jjvernon.com)

DamagedTrax

attack is the amount of time it takes for compression to happen after the signal goes above the threshold.

the release is the amount of time it takes the signal to reach unity gain once the signal has dropped under the threshold, after compression has happened.

thats what i was always told but then again pluto isnt a planet anymore and koalas arent bears these days... so who knows?

madtheory

It's a confusing one to explain, but Mr. Izhaki is right. The threshold is not "the level", the level is the threshold multiplied by the ratio. Remembering that a ratio is a fraction.

JJV

madtheory wrote: »

It's a confusing one to explain, but Mr. Izhaki is right. The threshold is not "the level", the level is the threshold multiplied by the ratio. Remembering that a ratio is a fraction.

Thanks, I think that helps. So if the ratio is 4:1 & a signal exceeds the threshold by 4dBs it will have its level brought down to 1dB above the threshold. Once this has been done is the release stage triggered?

Thanks

JJ (www.jjvernon.com)

old gregg

sorry to semi hijack the thread for a moment but does anyone know whether/where I'd score a copy of the "Mixing Audio - Concepts, Practices & Tools" by Roey Izhaki in Dublin?

I can get it on the 'net no probs but will be in Dublin tomorrow and figured on picking it up if I can. Thanks.

JJV

I think you'd do well to find one in Dublin. Got mine off Amazon.

old gregg

I figured that would be the case but had a shot-in-the-dark notion that I could sit back with a beer and enjoy reading it on the train down from Dublin

jtsuited

you MIGHT get lucky in hodges figgis. I've seen some fairly specific books in there on the topic over the years.