Born in Brooklyn, New York, a fortuitous move at the age of five brought Conlan and his family to Los Angeles to set down new roots. At the age of eight, a tortuous, stilted regimen of piano lessons began, but by age eleven a new, younger teacher had opened Conlan's eyes to the more theoretical dimensions of music and the magic of chords.
Conlan began to hone his craft as early as high school, writing music for various ensembles and choirs. But it was not until a friend introduced him to Earle Hagen's seminal book, Scoring for Film, that Conlan realized how he should apply his passion.
After a few years of writing commercial jingles for Santa Barbara radio stations, Conlan began to work for Hagen on the TV series Eight Is Enough. This introduction to television led him to work with composers Mark Snow on Starsky & Hutch and Hart to Hart and Hoyt Curtin on Hanna-Barbera's Smurfs and Popeye. Conlan's first screen credit soon followed when Barry De Vorzon brought him on to write the score for the new series Simon & Simon.