help with hz to octave conversion for dsp

Re: help with hz to octave conversion for dsp

When doing that am i looking for a somewhat flat response? If doing a TF i presume my reference measurement is off the desk?
 
Re: help with hz to octave conversion for dsp

BJ James said:
Yorkville was good enough to get back to me with q values, and they appear to make much more sense then the numbers i came up with when converting. Apparently you can't just divide freq by hz to get the q ......when i did that with a set of numbers i came up with a q of 41 where Yorkville provided a more reasonable q of .75 for the same numbers.
Click to expand...

Glad you made progress. Your mention earlier of a 5Hz bandwidth at 200Hz was certainly highly dubious so what we took to be -3dB bandwidth values evidently weren't.

Nick
 
Re: help with hz to octave conversion for dsp

BJ James said:
When doing that am i looking for a somewhat flat response? If doing a TF i presume my reference measurement is off the desk?
Click to expand...

if your computer is the signal source, then you go out of the computer, split the signal (or do internal loopback) to the ref input and the DSP input, then take the DSP output to the measurement input.
with no settings applied it should measure so flat that it almost looks wrong (don't forget you still have to adjust smaart's delay settings because there is some delay in the DSP (and that can change every time you change filters)
now you can change filter settings in the DSP and watch in realtime what it is actually doing (vs what the DSP may tell you that it's doing)

Jason
 
Re: help with hz to octave conversion for dsp

Jason Lavoie said:
if your computer is the signal source, then you go out of the computer, split the signal (or do internal loopback) to the ref input and the DSP input, then take the DSP output to the measurement input.
with no settings applied it should measure so flat that it almost looks wrong (don't forget you still have to adjust smaart's delay settings because there is some delay in the DSP (and that can change every time you change filters)
now you can change filter settings in the DSP and watch in realtime what it is actually doing (vs what the DSP may tell you that it's doing)
I

Jason
Click to expand...

I have been running pink noise off an ipod(Bink's wave file) split to the desk and my USB interface. Usually a measurement mic on the USB interface as well. So I can/should just take the outs of the DSP and do individual TF of each band? Then can I overlay them to view?
 
Re: help with hz to octave conversion for dsp

BJ James said:
I have been running pink noise off an ipod(Bink's wave file) split to the desk and my USB interface. Usually a measurement mic on the USB interface as well. So I can/should just take the outs of the DSP and do individual TF of each band? Then can I overlay them to view?
Click to expand...

yes. you'll have to pad the interface's input of course for the line level signal but in essence you're making the same measurement as always, except you're measuring earlier in the signal chain.

the overlay won't be the same as the sum, but it will be a helpful picture. if you have smaart 7 you could measure all of your output bands simultaneously and show the sum.

Jason
 
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