[PD] basic resonant filters in Pd

[brandon zeeb]

I've verified my calculations and duplicated the ggee code in a short perl
script.  My script and my Pd patch match, but are still off from ggee.
I feel like a noob here, what's the difference?

The script/patch are being compared at 100hz, bw=1, sr=48000.

~Brandon

On Sun, May 17, 2009 at 9:45 PM, brandon zeeb <zeeb.brandon at gmail.com>wrote:

> Hey,
>
> I've implemented the same coefficients as the ggee [lowpass] external in
> Pd, and can't seem to figure out where my calculations are off.  The
> calculations are in the [pd lowpass] sub patch.
>
> Any ideas?
> ~Brandon
>
>
> On Sun, May 17, 2009 at 2:43 PM, Frank Barknecht <fbar at footils.org> wrote:
>
>> Hallo,
>> brandon zeeb hat gesagt: // brandon zeeb wrote:
>>
>> > Good call!  I explored the GGEE objects in Pd-extended, which led me to
>> > their source code (A+ for readability),  which led me to this:
>> > http://www.musicdsp.org/files/Audio-EQ-Cookbook.txt
>>
>> The filter objects in the rjdj-lib just do these calulations as pd-vanilla
>> abstractions (no stability checks)
>>
>> Ciao
>> --
>> Frank
>>
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>
>
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