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Discussion Starter #1
Hi JohnM and thank you for the fantastic REW.

I started to write an open source software DSP with HDMI output for the Raspberry Pi that would rely on REW for room correction via IIRs.

The DSP would run at 96 kHz by default or another sample rate depending on user settings.
Generic Equaliser would be best selection as it allows to runs the auto eq with many filters and highest precision.

However since REW Generic EQ is based on the Audio EQ cookbook's formulas, the outcome from the same center frequency, gain and Q settings are very different for high frequencies depending on the output sample rate chosen.
Attached, the predicted response and filters for Generic and MiniDSP 2x4 HD targets for the same peaking EQ.

Is Generic hard-coded for 48 kHz output?
I hope it is possible to add a sample rate selection for it like in an additional drop-down that would allow the auto eq to do its magic at the desired output sample rate.
The current sample rate, only available when exporting to coefficients occurs too late.
Generic-44100, Generic-48000, Generic-96000, Generic-192000 instead of only Generic would also do the trick :)

As an alternative approach, have you considered integrating formulas which match analog filter frequency response better near nyquist?
EQ10Q has a very good one: http://eq10q.sourceforge.net/?page_id=60
An added benefit is that the gain at nyquist doesn't have to be zero anymore.
 

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Yes, the Generic EQ is 48 kHz. TMREQ, MiniDSP-96k, MiniDSP-2x4HD, nanoAVR are all 96k, as is the rePhase setting in the latest beta.
 

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Discussion Starter #3
Cool, I was unaware of the new V5.17 beta 12 (the previous beta says its up to date)

I tried the rePhase setting with good results against the simulated measurement attached, especially by guiding the auto eq with which frequency bands to use.

Hopefully you'll consider adding Generic-96000 option with a very high number of filters available, >20 for high resolution full-range correction.
That would be the best recommendation as IIRs are best for real-time processing.

Planning to test further the EQ10Q coefficient generation technique and integrate it as option: It could be a worthy alternative to rePhase FIR, getting near constant-q with IIRs instead.
 
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