[PD] Compressor for vanilla pd??

[Andy Farnell]

On Tue, 2 Dec 2008 17:59:42 +0000
"Solen Music" <solenpuredata at googlemail.com> wrote:

> Does anybody know if there's any theory about soft knees, program
> related releases, etc., so as to maybe emulate opto style compression
> or other types of esoteric compression?


Putting a low pass filter of a few Hz into the side chain can provide 
an attack. To soften the knee you need a smooth transfer function that
multiplies the gain curve (so its a sort of second order thing). Places
a curve between the linear 1:1 gain and reduced gain 1:n lines.

Opto is a feed forward style, and IIRC the photoresistor (ORP12 CdS2)
has a slight persistence so it responds sluggishly to changes.
I'm not sure if that's actually due to the slow cooling of a filament
lamp some designs use one, but others use a LED which seems
to be instant on/off)

Anyway, you could model feed-forward in Pd using a small delay buffer
and a lowpass filter.





-- 
Use the source