Trombonist Norman Bolter has a good memory of how old he was when certain things happened to him. The longtime West Roxbury resident was first enamored of the trombone when he was 4 (he saw Mr. Greenjeans playing one on “Captain Kangaroo”).

He got his first one and began formal lessons when he was 9. He decided he wanted to be in an orchestra when he was 10. He composed “The Song of King David” when he was 12. He played the piece for the personnel manager of the Boston Symphony Orchestra when he was 13. He joined the BSO at 20. Now 56, Bolter retired from the BSO in 2007.

Q: You’re from Minnesota. What brought you to Boston?

A: I went to New England Conservatory, but within two weeks of coming to town, I saw a notice on the bulletin board about all these auditions. I thought I’d audition, and I got them all. Springfield Symphony, first trombone. Then I got into the Boston Ballet, Opera Company of Boston, and the Cambridge Brass Quintet. I was doing so much work that it was hard for me to go to school and still practice four or five hours a day. So I left school.

Q: What else do you play besides trombone?

A: Euphonium and didgeridoo.

Q: You also do a lot of composing.

A: I compose to get closer to the subject matter or the feelings that I want to get close to. Music is such a transferable type of energy. It’s healing. It has many different attributes.

Q: And you wrote a piece for didgeridoo.

A: I wrote “Ancestors,” a trio for didgeridoo, ram’s horn and serpent, which is an instrument that was used a lot in the church, way back; it looks almost like a bassoon but it has a trombone-type mouthpiece. We did “Ancestors” a number of years ago at New England Conservatory. It was a very atmospheric piece; people couldn’t even move after we played it, all of these sounds that you’re not used to hearing coming together.

Q: Trombonist Doug Yeo says you are the loudest trombone player on the planet, should you wish to be.

A: (laughs) That used to be a pretty good assessment. I think some of it came from a combination of things. When I lived on a farm in Minnesota for a while, I’d go outside, and that’s where I did a lot of playing. The fact of wanting to play loud was kind of a flight for me. I used the trombone to take out every emotion. I used it to vent – everything from sadness to happiness to humor to mischievousness to anger and frustration. John Williams used to like my loud playing a lot. When he first heard me he called me the superman of the trombone.

Q: You played a lot of popular music when you were with the Boston Pops. Are you a fan of that style as much as classical?

A: Tommy Dorsey really had an unusual thing going on. The smoothness and the lyricism, and the incredible finesse was astounding. They used to call me the Jewish Dorsey. I also listened to J.J. Johnson. In fact, when I was 9, before I wanted to be a classical player, I wanted to be like J.J. Johnson. But my mother had a recording of the “William Tell Overture.” There’s a huge trombone part in the storm scene that’s on every trombone audition. She put that on our little hi-fi, and as soon as I heard that I knew I wanted to be in an orchestra.

Q: Why did you leave the BSO and the Pops?

A: I loved playing in the orchestra. I loved the music, I loved playing with John Williams and Seiji Ozawa, who was brave enough to take such a young man into the orchestra. But I have other callings in music that I think serve a greater purpose than me just playing in the orchestra. I teach trombone and chamber music, I coach a brass section in the orchestral literature, and I have a trombone class. My wife, Carol Viera, and I started the Frequency Band, which currently has 23 trombones. I’m composing, different orchestras ask me to play with them, and I still have to practice.

Norman Bolter’s blog is at http://frequencybone.blogspot.com.