an interesting thread indeed.
I think the bottom line that everybody hears music differently. in fact, I
know that people hear music / sounds differently. I'm not talking some kind of wishy-washy "we all connect differently on an emotional level with different artists blah blah blah" kind of variation here - I'm talking variation in the chain: sounds -> ears -> brain = music.
I'll start a new thread with a little experiment (which might go horribly wrong!).
it's interesting to hear people talk about how little they understand, or want to understand, the mechanics of song writing, arrangement and recording. of course, it'd be naiive to assume that everybody listens to a song and can pick out the bassline, or notice a shaker dropping in and out of the mix, but it's good to be reminded in clear terms that for the vast majority of people this is not the case.
I suppose I take it for granted - I can remember listening to simon and garfunkel at a very early age and thinking "hey - they're singing the same words, but different notes. that's pretty cool". I can remember seeing Black Box on TOTP or whatever and thinking "hey - that woman's not really singing that! and they must have used some kind of machine to make her voice go all stuttery"... I never really had any proper musical training (stopped having instrument lessons before my teens, never really got into theory or grades). but I've been learning about the art and the science of music-making and recording ever since those early days - the concept of multitrack recording, the art of arrangement, the concept of sampling.... the list goes on. I find this stuff fascinating, magical and useful.
as far as having a "trained ear" goes, I think it's wrong to assume that understanding how sounds are played, recorded and mixed decreases your basic enjoyment of a recording, just as it's wrong to assume that
not understanding these things means you appreciate music less. both opinions carry with them some kind of ignorance or arrogance.
the best way for me to break it down is like this - it's all about accepting and appreciating the lines that can be drawn between:
the instruments
the musicians
the songwriter
the song
the production
the recording
so, to clarify - whilst my appreciation of the production of a recording might be greater than that of someone who knows little about these things, my appreciation of a song (or to be even more anal, a particular recording of a song) is exactly the same - either I like it or I don't. that's the stage where it comes down to sounds -> ears -> brain = music.
I'm sure everyone could name certain recordings of certain songs that they believe are better than other recordings of the same songs (cover versions / alternate takes / remixes / live versions). you might not be able to describe why in any kind of technical terms, but that doesn't matter - the technical terms are for those interested in the technical side of the process. most people aren't interested in this side. but as I point out above, I see that as crossing a line into a whole new area of music.
perhaps it's most like following the mic cable from the stage to the sound desk - you're still at the gig, and can still be listening to the same things as everybody else, but perhaps you now have something different to think about the next day.