Being the musical egghead that I am, I tend to be very fond of Frank Zappa's thoughts on composition. In particular, the idea that anything can be music. Yes, anything — "Anything can be music, but it doesn't become music until someone wills it to be music, and the audience listening to it decides to perceive it as music. Most people can't deal with that abstraction — or don't want to."
Zappa goes on from there to his complaint about people wanting what they know. It's sort of true, although I don't really get as worked up about it as he did. Hey, some people just want to have some fun, challenge not being a requirement for every listening experience. Count me in that camp too. Heck, I finished out the work day a couple of days ago with some Commander Cody. Who needs high art when you're only looking for a smile and a shot of the energy of the familiar?
Somewhere in between these ghettos of art (both low and high) lies the loft of music concrete. It's a form (hmmm...almost hate to use that word here) of composition that gets its source material, concepts, and sounds from the real world and its goings on. The screech of subway brakes, the chirp of birds, the rattle of industrial equipment. The RPM Orchestra reminds me that these concept have always held a lot of resonance. Not only do I experience unusual things as music, but often I hear bits of "normal" music emanating from their intersections.
The idea of extending the definition of music so that it pushes back into everyday objects and situations isn't all that outlandish. Not too many years ago, Steve Reich built a composition based on words being spoken about a train trip to Chicago. Yes, Different Trains was quite an ear-opener. More recently, there is Nico Muhley's Mothertongue.