Trace Arithmetic Issue

[Audio_Guy_UofW]

Hi, I have seen an issue with trace arithmetic. As per a previous post, I have been using |A|/|B| to normalize a speaker response. I have been using the most recent Beta to correct for an import error on sweep import. I recently had a crash when trying to save some jpeg images, to the point where the icon was removed, the executable file appeared to be removed, and I had to re-install from the previously downloaded file.

Seemed to be working OK, but today when I went to generate some new equalized curves, I went through the procedure of subtracting the 1kHz level to get a 0dB normalized curve, then using this to apply |A|/|B| to the measured curve. Instead of making no difference to the curve at 1kHz, it subtracted the original value of the curve. See attached data file. I have seen this behavior before sporatically and relaunched REW. THis time seems more persistent. Any input appreciated.

 

[John Mulcahy]

I don't understand what you consider to be wrong about that result? Dividing a response by something that is 15 dB louder will give a result around -15 dB. If you want a result around 0 dB align the levels of the responses before dividing them or shift the result to be at 0 dB in your chosen region.

 

[Audio_Guy_UofW]

Thanks, my mistake. I was sure I had subtracted the 1kHz value...but not. All good now.