6-pole switched capacitor filter "Q's" (literally)

Paul Perry pfperry at melbpc.org.au
Thu Mar 27 05:47:49 CET 1997

At 01:38 PM 31/12/98 -0800, Duane R Balvage  wrote:

>Can you loop the output through a VCA or variable attenuator back to the
>input for a resonance control? Or will the switched-cap filter freeak
>out if you do that? Anyone tried this? I don't have the chips yet, but I
>was thinking of trying this.

You can make a positive fedback configuration with ANY filter known.
When you get the loop above 1.0 gain at some f and it oscillates, what 
matters is this:
where in the loop does something saturate?
If the saturation is in your switched cap filter, it might sound good or
bad, who knows. But, depending on config, it need not saturate in the filter.

paul perry melbourne australia

(encouraging you to put your 31 band eq in a positive feedback loop)

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