First of all, let’s commend David for his honesty. Unlike many audiophiles who are certain that they can hear a difference in SQ, even where there is none, David was willing to put his beliefs to the test.
I received the files in question from David. First, I removed the metadata (which surely differs between the two).
% ffmpeg -y -i '14 - Nashville Cats 1.WAV' -map_metadata -1 -codec copy a.wav
% ffmpeg -y -i '14 Nashville Cats.wav' -map_metadata -1 -codec copy b.wav
Now, let’s check that they are the same length:
% ls -l a.wav b.wav
-rw-r--r-- 1 distler 27647838 Dec 18 09:14 a.wav
-rw-r--r-- 1 distler 27647838 Dec 18 09:14 b.wav
So far, so good. Alas, an examination in Audacity points out a problem: there’s a 12ms time-shift between the two files (12ms more silence at the beginning of b.wav; 12 ms more silence at the end of a.wav). They’re the same length, but they’re not quite the same.
That’s not a problem. We can trim the silence from the beginning and end of both files.
% ffmpeg -i a.wav -af silenceremove=start_periods=1:stop_periods=-1 c.wav
% ffmpeg -i b.wav -af silenceremove=start_periods=1:stop_periods=-1 d.wav
Let’s check that the files with the silence removed are still of exactly the same length.
% ls -l c.wav d.wav
-rw-r--r-- 1 distler 27069974 Dec 18 10:07 c.wav
-rw-r--r-- 1 distler 27069974 Dec 18 10:08 d.wav
Great! OK, but are they the same?
% sha256sum c.wav d.wav
1b7ef363eeaee1b6e3dea359c3ba983a0b989075a7a59804896f6af63aa26763 c.wav
1b7ef363eeaee1b6e3dea359c3ba983a0b989075a7a59804896f6af63aa26763 d.wav
Yup! They are exactly byte-for-#@%&-byte the same.
So, what does that teach us about the ability of even the most honest of audiophiles to fool themselves?
If you’re not willing to put your beliefs to the test, then you are almost certainly fooling yourself.