[sdiy] State Variable Filter self oscillation

[patchell]

    One of the thoughts I had to solve this problem was to add a little
bit of positive feedback in the path that controls the Q...at low Qs, the
negative feedback would dominate, of course, at the higher Qs, in stead of
having very little feedback, there would be just a very slight amount of
positive feedback, maybe even with some sort of limiter to help control
the amplitude of the oscilations....but, I have never tried this...

John Blacet wrote:

> Has anyone built a classic state variable that can oscillate?
>
> I have a few versions of this filter that get close but do not sustain
> an oscillation.
>
> Still poking around the breadboard, but any comments?
>
> Regards,
> --/////--
> John Blacet
> Blacet Research
> http://www.blacet.com

--
 -Jim
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