Measuring the "sound signature" of two different digital sources (DSD 2.8MHz)
Recently, I was able to identify an audible difference between two different integrated amplifiers with very good "blue zone" 5W SINAD while running in the 50 milliwatt to 5 watt range. I showed that the differences were measurable. repeatable, and met the threshold for audibility.
www.audiosciencereview.com
The digital source for those three systems was the Marantz SA-11s2 which I measured here and compared to the Panasonic UBP-UB9000.
www.audiosciencereview.com
Unlike the two integrated amplifiers, I could not hear a meaningful difference between these two sources.
So, what happens if we compare to two?
Test setup
Marantz SA-11s2: Outputs 5V at the XLR outs
Panasonic UBP-UB9000: Outputs 2V at the XLR outs
Recorded to E1DA Cosmos ADC Grade A
This volume mismatch will EXAGGERATE any differences.
Thankfully @pkane's DeltaWave will correct this for us.
As recorded
Initial peak values Reference: -9.642dB Comparison: -0.59dB
Initial RMS values Reference: -32.143dB Comparison: -23.096dB
After normalizing volume using DeltaWave
Final peak values Reference: -9.642dB Comparison: -9.632dB
Final RMS values Reference: -32.143dB Comparison: -32.137dB
Music on test: Concerto symphonique No. 4 in D minor, Op. 102: Scherzo from SFS0060 - Masterpieces in Miniature (Physical SACD) & DSD extract
I'll keep it simple:
-50 dBFS is the threshold for audibility for the PK Error Metric.
There is no subjective audible difference between these two DACs.
There is no measured difference between these two DACs with test tones.
There is no measured difference between these two DACs with musical content that was able to demonstrate differences between two different integrated amps.
Conclusion
Whew. These kind of negative results are actually very valuable. Being able to show that there is a difference between integrated amplifiers and simultaneously showing that there is NO difference between two high performance DACs gives me even more confidence in the ability for DeltaWave to measure and quantify audible differences that aren't readily apparent between test tones.
Thanks @pkane for the wonderful, free software!
@amirm
@pkane
Recently, I was able to identify an audible difference between two different integrated amplifiers with very good "blue zone" 5W SINAD while running in the 50 milliwatt to 5 watt range. I showed that the differences were measurable. repeatable, and met the threshold for audibility.

Measuring the "sound signature" of two different integrated amplifiers.
@KSTR figured out that the left and right channels were swapped during recording! Presumably this must have been the case when listening too! The calculations had been done in stereo. This changes the numbers and shows smaller changes between amps when fed directly but still has a change...

The digital source for those three systems was the Marantz SA-11s2 which I measured here and compared to the Panasonic UBP-UB9000.

Marantz SA-11s2 Review (SACD Player; Seiko NPC SM5866AS Monaural DAC)
Marantz SA-11s2 Review (2008-era SACD player with Seiko NPC SM5866AS Monaural DAC) Disclaimer: This review is limited by the limited availability of physical SACD test/diagnostics discs. DACs are all about precision Before there was hi-fi, the battles of engineering and craftsmanship lay in...

Unlike the two integrated amplifiers, I could not hear a meaningful difference between these two sources.
So, what happens if we compare to two?
Test setup
Marantz SA-11s2: Outputs 5V at the XLR outs
Panasonic UBP-UB9000: Outputs 2V at the XLR outs
Recorded to E1DA Cosmos ADC Grade A
This volume mismatch will EXAGGERATE any differences.
Thankfully @pkane's DeltaWave will correct this for us.
As recorded
Initial peak values Reference: -9.642dB Comparison: -0.59dB
Initial RMS values Reference: -32.143dB Comparison: -23.096dB
After normalizing volume using DeltaWave
Final peak values Reference: -9.642dB Comparison: -9.632dB
Final RMS values Reference: -32.143dB Comparison: -32.137dB
Music on test: Concerto symphonique No. 4 in D minor, Op. 102: Scherzo from SFS0060 - Masterpieces in Miniature (Physical SACD) & DSD extract
I'll keep it simple:
-50 dBFS is the threshold for audibility for the PK Error Metric.
There is no subjective audible difference between these two DACs.
There is no measured difference between these two DACs with test tones.
There is no measured difference between these two DACs with musical content that was able to demonstrate differences between two different integrated amps.
Conclusion
Whew. These kind of negative results are actually very valuable. Being able to show that there is a difference between integrated amplifiers and simultaneously showing that there is NO difference between two high performance DACs gives me even more confidence in the ability for DeltaWave to measure and quantify audible differences that aren't readily apparent between test tones.
Thanks @pkane for the wonderful, free software!
@amirm
@pkane