Here's an interesting though - about how to test galvanic isolation (qualitative, not quantitative).
Turn the Audiophilleo, your DAC, and your computer on - select the DAC as your source and turn the volume up pretty loud.
DON'T PLAY ANYTHING.
Now, run some stuff on your computer, and listen to see if any funny noises are there to be heard
(if the isolation is flawed, then you would hear noises leaking through from the computer).
If your DAC mutes when nothing's playing, you could make up a WAV file that contained a very low level continuous tone;
now play that file and listen for other noises mixed in with it.
Assuming you hear something like funny noises that way,
connect up the Vaunix and see if they go away.......
How? Right now the problem I see with all of this is that if the Vaunix is improving the AP2 wPP there is either an issue with Phillip's design or some other phenomenon occurring.
I'd like to understand more on WHY there is any audible differences.
So far no one has given me a technical reason that makes sense (at least to me!). I can only suspect that its placebo (no offense) without listening to it myself (anybody got a spare Vaunix laying around for me to borrow for a week?).
I understand that AP is now looking into it to see if there is indeed an issue, so I await Phillip's analysis.
Floating point arithmetic would be my guess (perhaps 32 vs 64-bit). Same comment goes to DaveBSC.
In the end Currawong, most of it is placebo. There were some USB audio bugs in 10.6 that caused issues with various devices (clicking noise mainly). AFAIK, Lion+, the players should sound the same.
Setting up a DBT with a friend or significant others is easy if you truly believe you can tell the difference between players. Try it! Its a lot of fun! :-)
That's a nice idea.