Blue or red pill?

[testikoff]

A real PITA trying to align the analogue captures 1 & 2, but here are the spectral graphs:

 

- Spectra/delta (frequency range 20...88200Hz; logarithmic scale):

 

- Spectra/delta (frequency range 45000...50000Hz; linear scale):

 

 

- Delta closeup (frequency range 45000...50000Hz; linear scale):

 

Some strange spiking near ~48.5kHz frequency...

[testikoff]

Just now, manisandher said:

 

Great! Thanks for doing this.

 

 

Yep, that's the ADC doing something weird, I think.

 

So what are your thoughts on whether there should be any audible differences between the two?

 

Mani.

Not sure... Digital captures 1 & 2 are identical. Analogue captures are very close spectrally (especially in 20...20000Hz audible range), but not quite the same.

[testikoff]

4 minutes ago, pkane2001 said:

 

So I'm clear: you phase aligned the two analog captures in the time domain, and then subtracted one from the other and then did an FFT plot of the difference?

No, just lined up samples the best I could on time axis (almost impossible to do with all the HF noise present), plotted their spectra & then calculated spectral delta.

[testikoff]

4 minutes ago, manisandher said:

Enough of a difference to be audible in your opinion?

Not for me with my gear...

[testikoff]

17 minutes ago, manisandher said:

 

Do you have a delta closeup for 20Hz-20kHz?

 

 

Haha...

 

Mani.

Here you go:

 

- Delta closeup (frequency range 20...20000Hz; logarithmic scale):

[testikoff]

The waveform delta of of my loosely aligned analogue capture 1 & 2 excerpts is not great, admittedly... The excerpts spectral delta, however, shows no substantial difference in spectrum within audible range, so regardless of small differences around 400Hz noted by others, they will be extremely hard to discern when the actual track excerpts are played back (not their refined null-test result produced by DiffMaker), IMHO...