Organist, pianist, trumpeter, singer, producer, of jazz, house music, French song, disco, free jazz... Charlie O. has produced, with Luigee Trademarq, music for John B. Root's films, remixes for Alex Gopher or De Crecy, the soundtrack for a Cedric Klapisch film, collaborated with Cosmo Vitteli and David Grubbs, formed a group with Akosh S., ErikM and Quentin Rollet, co-produced a Mendelson album, participated in Rubin Steiner's "Chantiers", etc.