Behringer UMC204HD interface for RMAA DAC test

[oldpc]

Hi all, I tried to measure my USB-DAC Cambidge DACmacgic by RMAA and Behringer UMC204HD but the result looks not so good as i expected, and it's not same with other result that I found online about this DAC.
Note: i measure under mono mode, level input of line is about 10h.
Someone can help me to check this matter?
Thank you very much

 

[RayDunzl]

level input of line is about 10h

The Behringer creates its own distortion at higher input levels. At what dBfs level is the peak?

Did you apply the 10dB input pad?

Also, not sure what "10h" means here.

Some other discussion of the ADC in the Behringer here - https://www.audiosciencereview.com/...terface-suitable-for-measurements.7536/page-3

 

[sergeauckland]

I've tried now three different examples of the UMC device. My standard test is to connect output to input and run the RMAA/Audiotester/whatever test. With my Lexicon USB I-Onix U22 device I get very low distortion with output connected to input, and levels set to give about -1dBFS on the record input. It varies slightly with output level and input gain, but generally, it's well below 0.01% distortion, so low enough for Jazz.

With the UMC devices, I got something around 0.5% distortion on a back-to back test, and which varied a lot depending on the output level and input gain. It seems that the ADC part is the problem, not the DAC, although I couldn't get anywhere near Amir's figures on distortion of the DAC, nevertheless, DAC distortions were much lower than the ADC. I use a UMC at our radio station for Outside Broadcasts, where the ADC path is used only for cueing, so non-critical, but I wouldn't want to use the ADC for anything important, like making recordings.

S.

 

[oldpc]

The Behringer creates its own distortion at higher input levels. At what dBfs level is the peak?

Did you apply the 10dB input pad?

Also, not sure what "10h" means here.

Some other discussion of the ADC in the Behringer here - https://www.audiosciencereview.com/...terface-suitable-for-measurements.7536/page-3

I tried to keep it -1.0 DB as recommended by software.

 

[solderdude]

I also encountered similar 'issues' with RMAA after I changed my PC (and O.S.). It gave erroneous readings while the signal was still below the -1dB (it shows when it detects clipping which is clearly visible in the harmonics) and that did not happen.
It wasn't clipping just higher harmonics.
I tried several versions but gave up.
Have been using REW ever since. Also free software and less problematic but more complex to set up properly.

 

[trl]

The MIC input seems to be saturated, probably because of the output voltage coming from the Cambridge DAC. You might want to lower the output volume of the Cambridge DAC or use -3 dB or even -6 dB sinewaves for this test (or adjust RMAA levels accordingly). Also, INST will have a lower noise than MIC, so you might try to use that input instead.

Frans, with REW I always got worse numbers due ti it's internal generator. I find audiocheck.net 16/48 sinewaves as being better than REW's and ARTA's internal generators.

 

[Lilith]

Hi all, I tried to measure my USB-DAC Cambidge DACmacgic by RMAA and Behringer UMC204HD but the result looks not so good as i expected, and it's not same with other result that I found online about this DAC.
Note: i measure under mono mode, level input of line is about 10h.
Someone can help me to check this matter?
Thank you very muchView attachment 29962

View attachment 29963

I get basically the same result. Not good ...