Using offline measurement capability

[afilipi]

I’d like to measure the response of my car audio system using REW. The problem is that my head unit has no line-in, aux-in, or HDMI-in port, so I cannot use the same procedure I use for my home theater. Following the online help, I have exported a measurement sweep with timing reference onto a USB stick in WAV format, have plugged the stick into the head unit, and can play back the sweep.

The question is, what now? Should I record the played-back signal using something like Audacity and use the Import sweep recordings function in REW? When recording the signal, should I try to maximize the level without clipping, or is there some optimal target level?

What I have done so far is used the Measure function. I checked the “Wait for timing reference” box in the Make a Measurement window and clicked Start Measuring. I then played back the WAV sweep on my head unit. REW "heard" the timing reference and took a measurement. This procedure seems to work (except the dB level is clearly off), but I wonder if the frequency response calculated using this procedure is incorrect and I should instead exclusively use the Import sweep recordings function.

 

[John Mulcahy]

You've done the right thing, that method is fine.

 

[afilipi]

Thank you, John.