Voxengo - Sound with a Soul
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Hi,
I just bought HarmoniEQ, and am extremely happy with it, however I noticed something and I'm not sure whether it's a 'feature' or not:

When changing the Quality from Normal to High I notice the orange line changes slightly, from what appears to be 5Khz up - a slight boost is registered, (try this on the 'Acoustic Guitar' preset for a quick example) and the opposite happens when changing from High to Normal.

I hadn't expected this behaviour - is it working as designed?

Cheers

Yes, this slight curve change is unavoidable and works as it should.  It's not easy to avoid this.

Thanks Aleksey,

Can you please explain to me, unless it is a secret, how and why this is the result?

Again, thanks

This is caused by so called 'frequency warping' - it's an effect found in digital filters and caused when the center frequency of the filter is very close to the processing samplerate.  This can be resolved by increasing samplerate or by using some non-conventional filter design (that's usually not very practical).

Again,

Thanks.  I guess, until I start trying to understand DSP, I'll not be able to come up with a more practical solution which doesn't cause this frequency warping.. ;)

Thanks

You are welcome...  Just want to clarify a bit more:
It warps (folds) when the center frequency of the filter is close to the half the processing sample rate (for 44.1kHz it is 22kHz).  So, around this frequency filter changes its shape considerably.

I also want to add that I'm trying to find a good solution to this problem.  Hopefully this can be resolved at some point in the future.

Thanks for explaining those details, and I wish you luck (if you need it) finding a suitable solution.

Thanks :)