Hallo, Anton H?rnquist hat gesagt: // Anton H?rnquist wrote:
The filter response gets nasty and loud if the center frequency is near or above the sampling rate. Maybe it should be restricted as well. But then, resonance at 1 will make everyone jump, too...
Yeah I noticed that aswell. I think the Csound-version has cutoff restricted to 0...1, which is 0...11050 in hertz.
Only resonance is restricted to 0 and 1. It is in the pd version as well. I made some tests now and it seems it's not the cutoff frequency alone that makes the filter run wild. With resonance set to 0 a cutoff of 96kHz when running at SR = 48kHz doesn't go wild. But set resonance to 0.1 and it runs away.
So in the end I'd say, just be careful and if in doubt [clip~] your input values.
Another issue may be denormalization, so some PD_BIG_OR_SMALL checks could be useful.
Ciao
Frank Barknecht