Colin Hart has published on his blog an interesting interview with Bruce Tanis, sound designer of “Fringe”, a sci-fi show of Fox.
CH: How old were you when you discovered your passion for sound?
BT: I came to sound editing a bit later than most people I guess. I finished my degree in Forestry from the University of Nevada in Reno but this was in the early eighties when everyone through the seventies had wanted an “outdoor” job so the market was flooded. One of my professors at UNR was the film critic for our local CBS affiliate station and he taught a few film study classes which I took. He was kind enough to help me get an entry level production job at the station and I spent a few years there doing broadcast audio for both studio and live broadcasts. At some point I decided to go back to school because film and television were much more interesting and promising than my potential forestry career. I applied to all the standard film schools in the L.A. area and the only one who accepted me was the Art Center College of Design in Pasadena, California. While there, I got sidetracked into doing more camera work than sound but only for a year until I got a job at Cannon Films in the tv & promo dept.
Most of the work there was in pulling sound effects for the picture editors, going to online sessions and dubs and otherwise working in the sound world again. So I guess the simple answer to your question is somewhere in my early twenties with a couple of detours shortly after and then settling for good around age thirty!