After studying music for several years, both privately where he grew up in the Saguenay/Lac-St-Jean region of the Quebec province, and at the Lionel-Groulx College in the Montreal region, he began his career playing guitar, bass and keyboards, as well as singing in clubs around Quebec in the late 1980s and early 1990s with various local Top 40, rock and blues acts.
[1][2] During the same time frame, St-Gelais began to receive more and more calls from various jingle and production music producers requesting his services as a studio musician, vocalist and programmer.
Since then, he has worked with Marie-Mai, Celine Dion, David Usher, Roch Voisine, Randy Bachman, Melissa O'Neil, Rex Goudie, the Canadian Idol television series, Gabrielle Destroismaisons, Andrée Watters, Alain Dumas, Les Mecs Comiques, Annie Villeneuve, Lindsay Robins, Crampe en masse, Réal Béland, and the band Hépatite B, in which he is also the lead singer and guitarist.
[citation needed] St-Gelais, Lindsay Robins and Christopher Ward's song "Time Bomb," was named a finalist in the 2005 International Songwriting Competition (ISC).
[11] Along with Marie-Mai, St-Gelais was showcased at the Canadian Songwriters Hall of Fame 3rd Annual Gala, which was held February 5, 2006.