External Signal Mode

[Badbruno]

I'm getting ready to measure the analog frequency response of my phono signal path.

I was told that this is the approach of settings : Open REW — Select External Signal Mode. I can't find it...now I'm no expert and could use help in setting up to make measurements while using a vinyl test disk to providing a 20-20khz sweep track.

I would appreciate help in this setup configuration!








In REW:





Click Measure → a measurement window appears.





Now set:








• Sweep Type: “External”

 

[John Mulcahy]

Doesn't exist. REW has a mode to measure from a file played back externally, but the file is one generated by REW.

 

[Keith_W]

Would he be able to use the RTA John?

 

[John Mulcahy]

It's possible, but awkward. Need to select an FFT long enough to span the whole signal, use Forever averaging, run the RTA long enough for it to finish one complete acquisition before starting the playback, then stop the RTA when the playback ends. The peak trace may give a better view of the result.

 

[Badbruno]

I'll try it in a couple of days !!

 

[John Mulcahy]

You can get the setup right by using the REW signal generator to play a log sweep of the same duration and feeding that to the RTA.

 

[Badbruno]

Good suggestion rather than me cueing the vinyl track over and over again