Recent content by johny_2000

I did as you said, the distortion report became close to reality. Thank you!

And one more noob question: If I can't get 0.0 dBFS reading at my ADC input using signal path gain, how do I use -5.28 dBFS reading in THD+N reading? For example, N+D(A-wt): -124.5 dBFS - (-5.28 dBFS) = -119.22 dBFS or am I wrong? And what about THD+N(no-wt) = -118.1 dB or do I subtract/add...

This is essentially the gain response of an active notch filter. I also made my own frequency response file with a REW sweep and the 1 kHz point adjusted to 0 dB, but the difference was negligible (a fraction of a dB), but there were many more frequency points. I also tried using both in RTA...

I also have a calibration file applied to the input device channel that contains the following information: 12 70 0 18 35 0 20 33 0 22 31 0 25 30 0 30 30 0 40 30 0 60 30 0 100 30 0 150 30 0 250 30 0 500 30 0 700 30 0 800 30 0 900 25 0 950 20 0 995 0 0 1000 0 0 1005 0 0 1100 25 0 1200 30 0 1300...

Thank you, John. I unchecked option to limit the cal data. I checked option to apply cal data to the distortion. Also, I calibrated the output levels of signal generator and ADC. Neither of these made any difference to the RTA's distortion report. The only option that significantly changed the...

Also, I'm curious about these two settings in the Analysis Preferences tab: "Limit cal data boost to 20 dB" and "Apply cal files to distortion" My AES17 Notch calibration file reaches 30 dB values at certain frequencies. I don't have a PC nearby to see what they are currently set to, but how do...

Next step is I'll take a True RMS multimeter and measure the following voltages: - DAC output voltage, - AES17 Notch output voltage = ADC input voltage, - Actual ADC 0 dBFS voltage I have a feeling that there are some (minor) differences in the I/O characteristics of the devices. Here's why I...

Hi all, I need help understanding the parameterization of DAC measurements using REW RTA. I ran a series of measurements on a test DAC. In this case, DAC = RME ADI-2/4 Pro SE, XLR output +19 dBU = 6.904 Vrms. ADC = E1DA Cosmos ADCiso, Mono mode, 3.500 Vrms input = 13.1 dBU. AES17 Notch = E1DA...

Great addition! Can you talk more about this process in REW?

Thank you. It appears that using a mic(notch) calibration file is the way to keep the dB levels as they are. Since the notch manufacturer provides the REW calibration file, I can do this in no time!

This is the frequency response of a 1 kHz active notch filter.

So how do I interpret the THD+N measurements (in dB) when using a 1kHz -30dB notch filter? For example: DUT -> Notch 1 kHz -30 dB -> REW RTA with AES-17 standard notch option enabled. Let's say we got a measured THD+N of -120 dB. Does this mean DUT THD+N is -120 dB or does it mean DUT THD-N is...

I support this request. Since RME DACs now support the "ADI-2 Remote 2.0" app with the ability to load EQ files, this will ensure a very smooth transition of EQ settings from REW to RME DAC.

Sorry to bring up this old topic, but I can't find any more details about the need to use an external 1/10 kHz notch filter for this measurement? Should I use both (external and REW "Use AES-17-2015 standard notch") or not?

Thank you, John.