[PD] poles, zeros and gain

martin brinkmann Sat, 12 Apr 2008 03:19:03 -0700

hi pd-list!

i have recently tried to build some filters using cpole and czero, not
completely unsuccessfull (at least the lowpass sounds somewhat like a
lowpass...), but i have a problem calculating the right gain (or
attenuation) factor. for the lp it seems to work more or less (ok
for a subtractive synth, but still not good enough for effects etc.),
but the hp is either too lound for lower frequencies and low resonance,
or hardly audible.
i think there might be a better way to find out the right gain
than 'try and error'.
and its getting worse with more poles involved...
so is it possible to get the gain from the poles and zeros, without
calculating all coefficients?


bis denn!
   martin

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#X text -404 106 4/2008 martin brinkmann;
#X text -405 8 slightly crude (especially the attenuatiun factor) lowpass
filter design \, made without knowing too much of the math involved.
frequency is not very exact \, but at least it sounds like a reson
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[PD] poles, zeros and gain

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