[PD] 2 pole lpf with resonance?

ugur guney ugurguney at gmail.com
Wed Feb 14 10:19:55 CET 2007


# Hi, here is an abstraction that I made when I was learning about filters
and resonances. I used [fexpr~] but now I know using a [biquad] will be more
efficient and simple.
# But in this implementation you can't set the resonance at audio rate, it
accepts control messages.
-ugur guney-

On 2/14/07, Vreahli the Audio Bandit <vreahli at gmail.com> wrote:
>
> Hiya. Okay - so here's the skinny. I set out about a half hour ago to
> figure out how to set up a 2 pole low pass filter with resonance in
> Puredata. Looks like that's apparently set up with a biquad~ filter. I
> read through the rather handy looking information over here at
> http://www.musicdsp.org/files/Audio-EQ-Cookbook.txt. I came out of that
> a bit more confused than when I went in. I also bumped in to
> http://www.creativesynth.com/MAXMSP/001-SynthBuildingMSP/sbm_03.html -
> which left me drooling quite a bit more than when I went in. Is there
> any way to set up a LPF with a live-tweakable audio rate resonance and
> frequency setting while avoiding doing the biquad math by hand? I can't
> even figure out how to get my computer to crunch those numbers for me.
> Thanks in advance for helping me out with this seemingly simple yet
> convoluted question.
>
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