That's not just the CD vs. record issue, it's also the CD vs. mp3 issue. Digital is perfectly capable of preserving those details, although it takes quite a bit of space (I don't know what the storage comparison is for CD vs. record). I forget all the details from my audio class, but something about the way mp3s are encoded and compressed (along with bit rate) means that you lose the really low frequencies and the really high frequencies first. It kind of makes sense to me, because those frequencies aren't usually essential in a song; you can still understand the lyrics and hear most of the instruments without them, and quite a few listeners won't notice that they're gone (assuming they can hear them in the first place). However, that does mean that lower-frequency instruments and voices can lose some of their oomph, and losing higher frequencies can mean losing upper harmonics and changing the tone quality of what you hear. I would suspect that is why the mp3s seem "hollow." Of course, it's also possible that the CD mixing was just poorly done.

tl;dr Lossy compression, not just for JPEG.