Been experimenting with using REW as a linear phase FIR generator.

Basic idea is to use a measurement's inverse impulse response as the mag and phase correction. And then add a xover to that inverse.

So apart from a measurement, all that is needed are a couple of imports from rephase, a Dirac pulse (flat mag and phase trace) and the chosen xover.

It takes 3 steps of trace arithmetic, and then applying IR Windowing to the final FIR file.

I just posted a thread on the REW forum asking John M for further guidance...it outlines the steps and has a mdat that's the source of attachments below.

REW as FIR maker | AV NIRVANA

Anyway, first below is the lower HF section of my well known 4594he coax CD on xt1464. Measurement, inverse with xover, then result on same page.

The second is the VHF section.

The third is processed HF and VHF sections stitched together.

I thought I'd show water falls cause they are less boring than mag and phase traces and they are prettier

The last is the Dirac pulse and xovers needed from rephase (so folks can see how simple they are to generate.)

All the waterfalls are actual measurements, albeit electrical only.

I turned the actual measurement into a FIR file and put it in series with correction FIR file to get the final pretty outputs.

But if anyone is wondering, it works acoustically just as well, at least to a spot.

Same driver and horn, same process, acoustic results are here...https://www.diyaudio.com/forums/mul...g-horn-reflections-throat-16.html#post6027639

It's what has me on this REW process kick. Big thx again to nc535 for coming up with how to IR window for export as FIR.

I'm currently exploring how well it works for using REW FIR in IIR mode, without any latency...looking promising so far

One big caveat/warning...if you try this make sure you have a xover in place with the inverse, otherwise out of band amplitude can be destructive.

Same thing for "full range". Put some kind of high pass in till you're sure all is well.

Does anybody know a txt or wav, to bin converter?

Would like to try this with a minidsp unit also...

Basic idea is to use a measurement's inverse impulse response as the mag and phase correction. And then add a xover to that inverse.

So apart from a measurement, all that is needed are a couple of imports from rephase, a Dirac pulse (flat mag and phase trace) and the chosen xover.

It takes 3 steps of trace arithmetic, and then applying IR Windowing to the final FIR file.

I just posted a thread on the REW forum asking John M for further guidance...it outlines the steps and has a mdat that's the source of attachments below.

REW as FIR maker | AV NIRVANA

Anyway, first below is the lower HF section of my well known 4594he coax CD on xt1464. Measurement, inverse with xover, then result on same page.

The second is the VHF section.

The third is processed HF and VHF sections stitched together.

I thought I'd show water falls cause they are less boring than mag and phase traces and they are prettier

The last is the Dirac pulse and xovers needed from rephase (so folks can see how simple they are to generate.)

All the waterfalls are actual measurements, albeit electrical only.

I turned the actual measurement into a FIR file and put it in series with correction FIR file to get the final pretty outputs.

But if anyone is wondering, it works acoustically just as well, at least to a spot.

Same driver and horn, same process, acoustic results are here...https://www.diyaudio.com/forums/mul...g-horn-reflections-throat-16.html#post6027639

It's what has me on this REW process kick. Big thx again to nc535 for coming up with how to IR window for export as FIR.

I'm currently exploring how well it works for using REW FIR in IIR mode, without any latency...looking promising so far

One big caveat/warning...if you try this make sure you have a xover in place with the inverse, otherwise out of band amplitude can be destructive.

Same thing for "full range". Put some kind of high pass in till you're sure all is well.

Does anybody know a txt or wav, to bin converter?

Would like to try this with a minidsp unit also...

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