Weird graphics on impedance measurement

[Stephen McLuckie]

Any idea what is causing this? The measurement seems OK but the display is distinctly weird. FR reponse measurements are fine.

 

[John Mulcahy]

Difficult to tell from that, possibilities include polarity inversion in the interface and monitoring being active.

 

[Stephen McLuckie]

Thanks, John. Could you advise me what to try to fix polarity inversion and active monitoring?

 

[John Mulcahy]

If the interface inverts polarity you can tick the Invert box in the REW soundcard preferences input options. A loopback measurement will show whether there is inversion, by looking at the impulse response with percent as the Y axis to see if it is the right way up. Monitoring may be controlled by the interface or its mixer software, on some interfaces there is a mixer knob of some form with input at one end and playback or DAW at the other. If there is such a knob it should be all the way around to DAW/playback. If monitoring is active that will also show up in a loopback measurement, as shown in step 5 of interface calibration.

 

[Stephen McLuckie]

Thank you. I'll look into it and see if I can fix it.