People who are really into music and have the ears for it (and perhaps the training, formal or self taught) can discern the differences between recordings on vinyl, cd, tape, and even MP3. I've never had the ears for it--too many ear infections as a kid. But vinyl recordings were produced for vinyl, and sound engineers balanced sounds and parts (I am sure I am flubbing the explanation--not my expertise) for how they would sound on that medium. When other media came along, recordings were 'remastered' to sound right on the new media. Some people can discern differences and can tell that something was lost or altered. I can't really, but admire people who have that ability.