Born in 1926, P_pin studied at the Conservatory of Music in Montreal, the Curtis Institute in Philadelphia and the Royal Conservatory in Toronto. In 1949 he won the Prix d'Europe, a Quebec government scholarship, and from 1949-1955 he studied in Paris with Arthur Honegger and Andr_ Jolivet. He also took Olivier Messiaen's famous class in analysis alongside Pierre Boulez and Karlheinz Stockhausen.

He is noted for his String Quartets Nos. 3 and 4, the ballets L'Oiseau-ph_nix and Le Porte-rê_ve, and his Symphonies Nos. 3, 4 and 5. Quasars (No. 3, 1967) and Implosion (No. 5, 1983) were commissioned by the Montreal Symphony Orchestra; according to the Citizen, a 1993 revision of La Messe sur le monde (No. 4, 1975) was his last major score.

P_pin was named an Officer of the Order of Canada in 1981 and an Officer of the Ordre national du Qu_bec in 1990.