- Listening to some music while doing other things is difficult because too intricate and detailed. One of my favorite CDs is a Bach album by Yo Yo Ma I have literally listened to 100s of times. Without fail it gets better every time I listen to it but I *cannot* do anything else (even driving). It feels like a fly buzzing around me.
- Emotional pull can be a negative when you are actively avoiding emotions. I actively hide myself from others when I'm in public, as the DC metro folks probably did. Aphex Twin, called a genius by everyone from Radiohead to Rolling Stone, has a broad music collection I have a very difficult time listening to passively because its so emotionally moving, especially his ambient work. Sometimes I just can't take it.
- Music of the best quality seems to require a certain amount of familiarity. Many of my now favorite albums are music selections I did not enjoy the first time I heard them.
- Great instruments don't mean great sound. The acoustics of the DC Metro station might not have brought out the best in a 3.2 million dollar violin. If you pipe his performance into the train station through crap speakers, nobody's going to notice it then either.