VCF not working [Willzyx kit]

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mmm
 
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Re: VCF not working [Willzyx kit]

Post by mmm »

For peace of mind you may want to check at the pin closest to C13 if you have also a signal too with Resonance set to min (though I'm pretty sure you'll have a signal there).

mavzz
 
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Re: VCF not working [Willzyx kit]

Post by mavzz »

Yes, I have a signal on that pin when I set Resonance to min. I found it interesting that as I turn Resonance down, the amplitude of the wave increases around two-fold when Cutoff is set min and around 5-fold when Cutoff is set to max. Is this to be expected?

Thank you VERY much for your help antto and MMM!!!

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mmm
 
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Re: VCF not working [Willzyx kit]

Post by mmm »

mavzz wrote:I found it interesting that as I turn Resonance down, the amplitude of the wave increases around two-fold when Cutoff is set min and around 5-fold when Cutoff is set to max. Is this to be expected?
I haven't checked if this is to be expected on this scale but in general a resonance increase leads to a level decrease.

Good filter designs compensate for this; for example by boosting the filter input level simultaneously. The xoxbox (and 303) take a different approach: The Resonance control doesn't only send the signal back to the ladder; it also sends the signal proportionally to the VCA in addition the to the "regular" filter output.

mavzz
 
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Re: VCF not working [Willzyx kit]

Post by mavzz »

Cool, that's really interesting to know! :D

Thank for all your help MMM!

Pish
 
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Re: VCF not working [Willzyx kit]

Post by Pish »

This looks like what I need to go through.

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