>but I'm not going to call the people who say they can tell the difference liars.
They're not liars, there are just 2 cases:
(a) They confuse harmonic and other types of distortion (e.g. from tube amps) or the extra compression applied to vynil as better than cleaner signal. Which, subjectively, might be.
(b) They are delluded (as opposed to liars), and wouldn't be able to perform their "tell the difference" in a blind A/B test.
On (a), the distortion arising from electromechanical systems tends to be mainly second harmonic, which people don't seem to mind. It gives a sine wave some "body" or "warmth".
Badly designed DACs tend to produce third harmonic distortion, which sounds "harsh" or "bright" (= like a cafe with lots of hard surfaces and people crashing their cutlery around).
There are very few badly designed DACs being manufactured any more, but the loudness wars have made music sound both bright and "lifeless" (lacking in dynamic range).
So yeah, (b). (B) has been found to be the case even among people who make audio equipment for a living. People hear what they expect or want to hear, just like with vision.
Edit: main reference: Floyd Toole, Sound Reproduction. Toole worked in an acoustics research lab for a Canadian government, and then ran Harmon Kardon's research lab for many years.
They're not liars, there are just 2 cases:
(a) They confuse harmonic and other types of distortion (e.g. from tube amps) or the extra compression applied to vynil as better than cleaner signal. Which, subjectively, might be.
(b) They are delluded (as opposed to liars), and wouldn't be able to perform their "tell the difference" in a blind A/B test.