MacOS measurement attenuation above ~10kHz

[belsamber]

Hi Team,
I am seeing a big cutoff in my measurements starting around the 10-11kHz mark - it looks like there is a low pass filter in place almost.

I believe this is an issue specific to REW on Mac (or alternatively I have some setting set somewhere in REW that is doing this.) Things I have tried:
- Tested with both stable and most recent beta of REW. Same results.
- Used both internal microphone and UMIK1 with REW. Same results.
- Tested with UMIK1 connected via powered USB hub and also directly to a single port USB-C adaptor (my Mac only has USB-C/Thunderbolt ports.) Same result.
- Tested that speakers are in fact generating the sound, and the microphone can pick it up, using Audacity (spectrogram view) and OpenSoundMeter. Looks good with these programs.
- Tested REW on my Windows computer with same UMIK1 and speakers - works properly without the cutoff.

Is there something else I should be checking here, or is this a known bug? I did search but couldn't find anything.

 

[Mike0815]

Hello,

here I do not see such a behavior wit my Mac setup. I do not use Umik but dedicated analog mics and various USB audio adapters though.
Did you check in this Mac Midi-App how the audio settings are?

 

[John Mulcahy]

Check the sample rates in Audio Midi Setup and make sure the UMIK is selected as the input device. If there's a significant latency in the playback path use the Acoustic timing reference option.

 

[belsamber]

Hi, thanks for the feedback. There's not much I can change in the Midi settings, but I have a screenshot below. I am also already using the acoustic timing reference. Any other thoughts?

Using the UMIK-1 on Mac is already painful with the inability to adjust the gain (not REW's fault of course.) I guess I might just need to use Windows for my measurements.

 

[John Mulcahy]

Quite odd, the measurement appearance is more like one would see with a source that is running at 24 kHz with the OS resampling it to 48 kHz. No issues using a UMIK-1 on my macOS test setup.