On Wed, Oct 18, 2006 at 08:28:15AM +1000, Erik de Castro Lopo wrote: > Dan Mills wrote: > > --- Erik de Castro Lopo <[EMAIL PROTECTED]> wrote: > > > > > You need a low pass filter on the control signal. It > > > should > > > be somewhere well below 1kHz. > > > > Agreed that you need the filter, but a 'brick wall' at > > 1Khz means that anything faster then 50ms or so as an > > attack time (and there are legit uses for such), will > > itself overshoot horrribly due to the gibb effect of > > bandlimiting the control signal. > > This is the way analogue compressors work. If you have a > sound with a fast transient going into a slow attack > compressor, the transient passes throught pretty much > untouched (apart from any clipping that may occur due > to other parts of the design).
Conversely, I'll just mention that it's possible to get distortion of low-frequency audio by setting the release time extremely fast, because the compressor is effectively trying to increase the gain at the end of every half-cycle. This is considered a case of giving the engineer enough rope to hang himself, and hoping that he uses it responsibly. See http://www.fmraudio.com/FAQ.htm#question4 for more. -- Paul Winkler http://www.slinkp.com
