DeltaWave null-testing audio comparator (beta)

[mansr]

13 minutes ago, pkane2001 said:

So it looks like you just need to be very careful about the settings in Audacity if you want unmodified data to be exported.

Yes, Audacity is very eager to apply its shaped dither to anything it touches.

[mansr]

12 minutes ago, Jud said:

Well now, it will be interesting to see whether an MQA file in one channel and a non-MQA file in another channel will even play back via Audirvana+ (which does the "first unfold" if set to detect MQA) or an MQA-enabled DAC; or for that matter whether a DAC or Audirvana+ would recognize an MQA stereo file mixed down to mono.

The MQA encoding uses both channels. If one channel is replaced, it will no longer identify as MQA.

[mansr]

2 minutes ago, Jud said:

OK, confirms what I was wondering about.  This makes good comparisons more difficult but not impossible.

Yes, you'll have to save the decoded MQA first, then use that for comparisons.

[mansr]

24 minutes ago, Jud said:

Exactly.  Tips on how?  

I use the Bluesound decoder on a random ARM device. For PC/Mac users, the best option is probably one of the many virtual sound cards that save the data to a file.

[mansr]

23 minutes ago, Arpiben said:

File 2 has one sample less than File 1.

DW is reporting 7 samples difference without any matching processing.

Sounds like something is limiting the number of samples to multiples of 8.

[mansr]

2 hours ago, pkane2001 said:

Adding MP3 reader took all of 5 minutes

Using which decoder? There's a lot of wiggle room in the spec, and some implementations are better than others.

[mansr]

Once you compensate for all the differences, no difference remains.

[mansr]

9 hours ago, pkane2001 said:

But that’s the point of DeltaWave -- to measure and to explain the differences. If no more differences remain, then they were all detected and reported. Goal reached 

Sure, but is the decomposition of the difference necessarily correct and meaningful? Suppose you run a sine sweep through something exhibiting a frequency-dependent phase shift. The result is indistinguishable from clock drift. What does your program report in this case?

 

I'm not saying your tool isn't useful. You just need to be careful interpreting the results.