Here is a great 1979 interview with Chet Baker from Les Tomkins and the JazzProfessional website. Chet talks about his reunion with Gerry Mulligan, his ear;ly years, and “Cool Jazz”. From the interview:
What originally caused you to take up the trumpet as your instrument?
My dad was a musician—he played guitar—and when I reached thirteen, his favourite musician was Jack Teagarden. So he brought home a trombone, but I was rather small for my age; I couldn’t make the positions, and the mouthpiece seemed so big. I messed around with it for a couple of weeks; then he took it away, and brought home a trumpet.
That seemed to be much more comfortable; I could get a sound—the smaller mouthpiece seemed to fit a lot better. I went to a little instrument training class for a year, and I played in the school marching band and the dance band.
When I was sixteen, I went in the army; for a year I played in an army band in Berlin, Germany. After discharge, I studied music at junior college, but at the end of a year–and–a–half I failed that—and I still play by ear. Although I can read, I don’t know the chords. I just hear them, you know, but if you ask me what the name of it is, I wouldn’t be able to tell you.