Truncated sweeps (v.5.30.2, macOS Sonoma 14.2.1, UMIK-1)

[all2ofme]

Hey all — just donated and joined

I'd been learning and measuring happily for the past couple of months, and sat down today to get into some subwoofer setup fun.

I can't for the life of me work out what's changed, but all of my 20–20,000Hz sweeps are playing in full but the mic (UMIK-1) seems to think they end early, meaning that the results make it appear as if my speakers don't do anything north of 7kHz. I found a few examples of others with similar problems, but none of the suggestions have worked for me.

As far as I can tell nothing's wrong with my setup, and I can't think of anything that I've changed. Until today my results would always be full range.

The system I've been testing on is a MacBook Pro via USB to:

• dCS Rossini DAC
• UMIK-1 mic (with its calibration file etc.)

What I've tried:

1. Unplugging and replugging all the cables.
2. Generating new preferences for REW.
3. Uninstalling then reinstalling REW (several versions back, as well as the newest).
4. Using an "Acoustic timing reference" (testing registers the initial trigger, but not the end one).
5. Generating and playing back from a file (REW doesn't seem to play the generated file — I assume I'm doing something wrong here, but can't work out what).

I've tried everything I can think of except asking you lovely lot

Ben

 

[all2ofme]

OK, I'm a twit. Of course I hadn't tried everything

I had family to stay recently, and hadn't noticed that the laptop I was using to test was now targeting my DAC as an Airplay target rather than using USB. (They're Spotify rather than Roon users...heathens.) Made sense for why the mic was done before the sweep tones were — the mic was hooked up directly and the sweep tones were seeing all sorts of network latency.

Back up and running again!

 

[John Mulcahy]

Good to hear its running. Acoustic timing reference would usually cope with that, there isn't a timing signal after the sweep unless the Analysis option to Adjust clock with acoustic ref is selected.

File playback is used when the file is played directly on the system being measured, not by REW.

 

[sm52]

Analysis option to Adjust clock with acoustic ref is selected

Do you recommend this option should be enabled at all times?

 

[John Mulcahy]

Yes.