Hi vliesgaard

>>What is "filter growl" (technically spoken)
> The amount of musical distortion the filter produces.
>
> 2 extreme examples: Minimoog filter a bit overdriven has a nice warm
> creamy character when you turn the cutoff knob. This makes the sound
> warm and bassy
> A cheap digital filter, witch produces hardly any distortion. And
> sounds therefore a bit less warm than a minimoog filter.

Ok, this will not be achieved by the filter itself, but by an level
change before the filter. You also might decrease the input resistor for
the audfiosignal (which would be the same).

More interesting is the answer of Ingo (ilanode).

Florian