REW as FIR generator experiments

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I don't think this is a bug it is just showing the truth which isn't so pretty, the dirac pulse is necessarily band limited at either end which is why the pulse is rounded at the top and bottom when you zoom in. The 1/A being a mathematical function is probably less limited which is why you see all the hash. My 1/A looks funky when zoomed out too, but when combined back it gives a perfect flat line, no wiggle even down below 0.1dB.

I only bought it up because I thought it might save you time dividing by dirac pulses, seems like that didn't quite work out :)

Thx again fluid,

So i hung with this 1/A stuff, really for the sole point of trying to learn more about sampling rate and impulse timing issues.
I think you are spot on right about the truth not always being so pretty with respect to how the impulse of correction filters can look.

Even though the 1/A impulse looks very bloated in comparison to clean looking inverse impulses I get from either the dirac/A or my FirD software, the results of 1/A look great.
All three methods look great really, with minutia differences.

The REW manual says 1/A is 20-20K limited. Dirac from rephase imports at about 24-22K. Not sure why dirac doesn't extend down to 10Hz...
I guess the minutia differences are due to these slight mismatched bandwidths...as mentioned..

Anyway, below is a close mic acoustical TC9 spectogram,
....via 1/A and its ugly impulse haha.
Works!
 

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