Damian Stewart wrote:
to answer my own question: use [biquad~] with coefficients taken from the [lowpass] external.
i while ago i have tried to build a resonant lp with biquad~, but had problems with clicks, when the coefficient were changed (even with quite slow changes). only very slow changes did not produce clicks, which is a little strange, since biquad-filters in my vst-plugins do not produce any clicks (and i compute the coefficients only every 96 samples or so (iirr), i use "the other" biquad form though.
i had better luck with the cpole/zero~ objects, the result sounded at least like a resonant lp, good enough for a little "squelchy bassline synth". though i still have not found out how to calculate the a0 (volume level scaling) coefficient right (and i could not get hold of the book that was reccomended on the list yet)
bis denn! martin