REW 5.20 RC4 sweep length causing frequency response issues..?

[Chuck Zwicky]

I have run into some anomalous results when performing some simple frequency response sweeps. I restarted REW to see if that would fix the issue, and I tried 2 different interfaces, a Thunderbolt UA Apollo and a USB Arturia AudioFuse.


Interface 1 Arturia Audiofuse Studio:

1M sweep 0-22.05kHz

1 rep: 11kHz response:

1M sweep 0-22.05kHz

2 reps: 16kHz response:

512k sweep 0-22.05kHz

12.2kHz response:

256k sweep 0-22.05kHz

1 rep: 2.4kHz response:

256k sweep 0-22.05kHz

4 reps: 20kHz response:

Interface 2 UA Apollo Twin:

1M sweep 0-22.05kHz

1 rep: 20kHz response:

512k sweep 0-22.05kHz

1 rep: 17kHz response:

256k sweep 0-22.05kHz

1 rep: 3.3kHz response:

128k sweep 0-22.05kHz

1 rep: 725Hz response:

 

[John Mulcahy]

Early cutoff of the response can have two causes: the capture missing the end of the sweep due to excessive replay and/or capture latency and the REW sample rate not matching the rate the device is set to in Audio Midi Setup. Reducing the REW buffer size setting in the soundcard preferences might help with latency issues, but the most reliable cure for that is to use the acoustic timing reference option, which ensures capture doesn't start until the timing signal is detected.

 

[Chuck Zwicky]

Thank you John, I'll check those things.

 

[Chuck Zwicky]

REW 5.20 RC 6

When making a screenshot the comment alignment is greyyed out when Comment position "On Image" is selected.

In a possibly related issue, the comment can obscure the THD window of the RTA, for example:

 

[John Mulcahy]

Comments on the image are always centred. For lengthy comments and/or to use html formatting choose the above or below image option.