Impedance calibration problem on REW 5.40 beta 54

[Antonio Di Motta]

Hello Johon

I found a problem with the impedance calibration.
The measurement works by manually setting the Rsense Rinput and Rleads parameters while the automatic calibration by performing the three steps Open circuit Short Circuit and Reference cal indicates at the first step a difference in level of the two channels greater than 59db and cancels the calibration.
Maybe there is some incorrect reference on the software?
I checked the presence of the signals between the two input and reference channels and they are the same.

Thanks, greetings
Antonio

 

[John Mulcahy]

Open circuit cal works when I try it. Can you attach a screenshot of your soundcard preferences?

 

[Antonio Di Motta]

Sorry not 59db but 3db I checked with but they are identical -10.42 db both channels.

 

[John Mulcahy]

As above, it works for me. If you attach screenshots of your Measure dialog and soundcard preferences I can make sure I am testing with the same settings.

 

[Antonio Di Motta]

here are the screenshots of the levels measured by Rew

 

[John Mulcahy]

If you attach screenshots of your Measure dialog and soundcard preferences I can make sure I am testing with the same settings

 

[John Mulcahy]

You can check the behaviour of each input by making a normal SPL sweep measurement of the measurement input and then the ref input while all the connections are set up for an open circuit cal measurement, perhaps one or both responses are not flat for some reason.

 

[Antonio Di Motta]

Hi Jhon,
I attach the sound card and measurement settings.
The levels of both channels are identical, I verified both by measuring the response with REW and with laboratory instruments.
I inform you that up to version 5.40 beta 29 everything worked well from version beta 30 it started to give the problem of the difference in level of the audio channels.
I hope it helps you.
Best regards Antonio