Possible to control freq via pot for RDFX/WRHX?

Algorithm development and general DSP issues

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Digital Larry
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Possible to control freq via pot for RDFX/WRHX?

Post by Digital Larry »

I figured out how to control frequency and resonance for two pole filters using MULX with a POT input, but these filters do not use RDFX or WRHX/WHLX.

Before I spend the rest of the day slamming my head into the wall I'm wondering if it's even possible to pot control freq and shelf with the RDFX/WR?X combination. If so, a hint would be vastly appreciated!

Update: nice section on this in the Knowledge base. Quick answer = it's a little more complicated.

http://www.spinsemi.com/knowledge_base/ ... ng_filters

This example covers adjusting the shelf depth via control. How about the frequency?

Thx,

DL
frank
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Post by frank »

Those instructions all require that the coefficient be part of the instruction so you can't use a register for it. If you want an adjustable filter you can't use these instructions and will need to use MULX.
Frank Thomson
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Digital Larry
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Post by Digital Larry »

Thanks so much for the clarification Frank. I do have the adjustable shelver working great finally.
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