Petit was born in a musical family. He started on cello at age six and attended the conservatory until age 15. At this point he turned his back on his classical upbringing. Hearing Sun Ra His Arkestra and Alan Silva's Celestrial Communication Orchestra had the power of a revelation and soon the cellist embarked on the avant-garde jazz train. He enrolled in the bassist's IACP. For the next ten years or so he studied there, then taught and performed administrative tasks, all the while playing in the CCO. During this period, he met saxophonist Michel Lobko who introduced him to the European scene of free improvisers. With him and Christine Janvier, he organized the first Décades de Musiques Improvisées in 1985, a first exercise in musical activism and networking. In 1990 he founded In Situ, a label he has pampered for 12 years before leaving Théo Jarrier in charge in 2002.
1990 is also the year Petit released his first solo album, Sorcier, on the British label Leo Records. A number of collaborations followed, including the avant-musical theater troupe Un Drame Musical Instantané. He developed a particularly strong relationship with bass clarinetist Denis Colin, playing in his trio since 1994. In turn he invited Colin to take part with saxophonist Daunik Lazro and drummer Michael Nick to his own quartet NOHC, the idea of which sparked in 1990. A first album came out in 1998 on In Situ, followed by NOHC on the Road on Leo two years later. A second solo album, Déviation, appeared in 2000 on La Nuit Transfigurée. ~ François Couture, Rovi