I started playing guitar at 9 or 10. My uncle worked for Fender guitars. He knew I was serious because I practiced all the time and never came up from the basement. He bought me my first guitar. At 11 I joined a local band called Chip and the Dips. I was a dip. Later I morphed into a percussionist and I took lessons at The American Conservatory of Music in Chicago. My teacher was James Dutton, who taught all of his students a totally comprehensive, soup to nuts education. We always had percussion ensemble work, and one day he assigned each of us to write an original work or arrangement for the ensemble. He liked what I wrote and actually paid me for it to use with his private band on the road. He was an influential teacher and this was the start of me composing. So I started composing simply because people thought I had talent. I was 18.
Then I learned that Roosevelt University had an electronic music studio with a couple of large Moog synthesizers. That's when I enrolled there as a composition major, piano minor. I knew nothing about the style of music or the requirements of the composition staff. I had blinders on for the Moog. My admission consisted only of auditioning for the chair of the piano department, no portfolio of compositions was required. I was 21.
I had two composition teachers, one for electronic music and one for "traditional." And by traditional I mean Berg and Webern. I was expected to devise stratagems, tone rows and the like, for my compositions. I didn't know what I was doing. It ran counter to my intuition, and my pop music sensibilities. Besides, I liked Stravinsky. And Stravinsky to a Weberner is trash. He would say to me, "Stravinsky would be nothing without the repeated note." I was allowed to write what I wanted, but at that age one writes to please the professor.
Positive or negative? A little of both. Over the years I've had MANY great teachers to whom I owe my gratitude. My EM teacher taught me the value of the musical "gesture," which is part of me now. But the Berg disciple taught me nothing. I only regret that I never received a solid grounding in counterpoint and the classical style. But being academia, somehow that was not as important as being avant garde. My piano teacher, I must say, taught me so much! Ludmilla Lazar, a Bartok wiz! is what a good teacher is supposed to be. When I told her that I wanted to play the Stravinsky Piano Sonata (which was clearly beyond my level) she didn't say no, she just gave me a concerned look, thought about it, and then a small grin. She said, You will have to work very hard to learn this. So I did and she was behind me all the way.
I had very little interaction with the orchestra for my compositions, just a few hours when you add it all up. I have always composed at the piano. Only recently, after selling my piano, do I use a DAW in conjunction with a notation program. This has opened up my world like you have no idea! Though I believe in teachers 100%, you probably know that all composers, regardless of structured education, are self taught.