When have A/B comparisons led you astray?

Last night I went to my son's Violin Master's Class.
Small venue - maybe 10 to 15 people present.
Piano and violin, that's it.
I have been listening to my digital source lately at home. I'm having trouble figuring it out. I know it doesn't sound real to me, but why?
What I am getting at is last night I feel like my ears woke up - again. The real sound is hard to describe but I feel that I am developing a sonic memory for it through training.
Ear training. My A/B comparison is moving toward Live vs. Recorded. Live is not a shifting reference. It is repeatable.
The Master's teacher was speaking about chords on the violin last night. A single note is in tune with itself. Only when compared or contrasted with another note can it be said to be out of tune.
To play a chord correctly on the violin, hold one note fixed and adjust the other to tune the interval.
So I agree. Does your system sound like live music?
Time will tell.

The recording process is the first step away from live, and the best equipment can keep that damage to a minimum down the chain, but once recorded it cannot be resurrected IMHO. Sure my system sounds like live music (unamplified acoustic), but I never confuse it for the real thing - A/B or Z.

Have you never - even for just one song - mistaken it for the real thing?

Wonderful? Moving? Enjoyable? yes. Real? Not so much.

How about when you shut your eyes, can you imagine that you are in the venue?
Sometimes I can.
With digital it's like I'm there but pixillated.
With analog, sometimes it works but usually there is smudge.