MOTM

> That's a limitation of the Moog filter design. Paul worked very hard
> to keep that behavior in to maintain the authentic sound.

Well, it's not just a limitation, it's also a feature. Without this, it
won't sound like a Moog Modular filter.
Actually it's not only the point where oscillation starts; it's also
frequency dependent nonlinearities when the filter is on the
edge to oscillation, and similar things. It's all linked - you
don't get one feature without the other. (I must know, because
it was me who worked very hard to maintain the
authentic sound. (;->) )

(You might have heard of a different approach, as used in a certain
polysynth, where the Moog-type VCF does also oscillate at lower
frequencies, and where you are advised to scale the resonance
feedback loop with keyboard tracking or modulation or whatever,
if you want to get frequency dependent resonance.
This does _not_ produce the Moog Modular VCF sound, however,
because it dosn't even have the chance to emulate the frequency
dependent nonlinear effects.)

JH.