[PD] biquad~ with elementary filters [was: Re: dinosaurs ...]

Damian Stewart damian at frey.co.nz
Sat Sep 20 14:09:18 CEST 2008

Charles Henry wrote:
> There's two problems with your patch.
> There's a sign error in one of the expr which calculates the imaginary value.
> The second problem (in the same expr) was a * vs / error ( you put "/
> 2*$f1" instead of / 2 / $f1).  Does that make a difference?
> Anyway, I jiggled with it enough to get it right.  Also, I put two
> other expr that check to make sure the poles / zeros are in fact
> complex rather than real.

cool, that's very nice.

however, there's some weird gain thing going on. check out the attached: 
notice how the left channel output (biquad~ output) drops gain, while the 
right channel output (handmade) does not.

any ideas how to fix this?
damian stewart | skype: damiansnz | damian at frey.co.nz
frey | live art with machines | http://www.frey.co.nz
-------------- next part --------------
A non-text attachment was scrubbed...
Name: beequad~v2-gaintest.tgz
Type: application/x-gzip
Size: 2802 bytes
Desc: not available
URL: <http://lists.puredata.info/pipermail/pd-list/attachments/20080920/d29332b1/attachment.bin>

More information about the Pd-list mailing list