REW Pro Multi-input sweep measurements

[u.froemberg]

Hi,

If I carry out "Multi-input sweep measurements" and have selected the "Preserve relative timing" option, I get this timing for the first channel with the "Impulse response calculation" "Align t=0 to a sampling instant" and the alignment of the IR peak to t=0 for the other channels.

This is confusing for me, as the setting suggests synchronous timing for all inputs. Which timing reference exactly is meant in the description of the "Multi-input sweep measurements"? My attached example measurement only uses the highly accurate internal timing reference of the "REM Babyface Pro" for all inputs and outputs.

 

[John Mulcahy]

To get that the measurement would have to be made with no timing reference and "Set t=0 at IR start" selected on the Measure dialog, if you select "Set t=0 at IR peak" that should fix it.

 

[u.froemberg]

OK, if I select "Set t=0 at IR peak" instead of "Set t=0 at IR start", the measurements are synchronised but with t=0 at the peak. What I wanted to achieve was synchronous timing with IR identical to 0 for t ≤ 0, i.e. for absolutely causal IR. I solved this by deactivating "Preserve relative timing" in the "Input selection" dialogue. This was irritating, as I expected the opposite and I suspect that others might feel the same way.

However, considering the great and very useful software, this is only a minor comment and the beta version is even more fun!

Translated with www.DeepL.com/Translator (free version)

 

[John Mulcahy]

With preserve relative timing off in that situation each input is treated independently so any delays between them would be lost. I've made a fix for the next development build to respect the t=0 choice when measuring without a timing reference and with Preserve relative timing selected.

 

[u.froemberg]

Thank you for solving the knot.