[1] He began playing in his late teens, after he purchased a Gibson ES-125 electric guitar[2] and amplifier with his leftover tuition money earned from his summer job.

"[5] In 1964, he was accepted at the Berklee College of Music, where he studied composition and arranging with Herb Pomeroy and William Malloff,[6] graduating in 1969.

[7] He credits this period in Boston with his exposure to jazz musicians such as Wes Montgomery, Wynton Kelly, Jimmy Cobb, and Paul Chambers.

"[5] In 1970 he co-founded the fusion group Pacific Salt[7] with trombonist Ian McDougall, Don Clark (trumpet), Ron Johnston (piano), Tony Clitheroe (double bass, bass guitar), and George Ursan (drums).

The trio was the first Canadian group to tour the Soviet Union under the Soviet-Canadian Cultural Exchange Treaty.

[21] Other critics have noted Gannon's "slick, cool stylings",[22] and "studies in careful and complete orchestration.