From the first season in 1993, composer Charles Amirkhanian, OM's founder and artistic director, has consciously and conspicuously featured African American masters from jazz's experimental edge, such as Muhal Richard Abrams, Leroy Jenkins and Wadada Leo Smith, acknowledging improvisers on an equal footing with 20th century innovators like Conlon Nancarrow, La Monte Young and Lou Harrison. Berkeley guitarist John Schott, who presents his trio playing "Carving, Scraping, Changing" on Saturday's program alongside solo piano works by Myra Melford and Wendy Reid's "Tree Piece #55" for violin, muted trumpet and African grey parrot, believes that OM reflects the vision of its founder. The festival opener is Mark Appelbaum, a professor of composition and theory at Stanford who handcrafts sculptural electroacoustic instruments out of found objects that serve as muse and vehicle for his playful, absurdist and often strangely beautiful music. Mitchell, who has held the Darius Milhaud Professorship at Mills College since 2007, is the latest in an impressive line of groundbreaking artists connected with Chicago's Association for the Advancement of Creative Musicians to be featured at Other Minds. After introducing the piece on the Art Ensemble of Chicago's 1973 album "Fanfare for the Warriors," he used it for investigations into the outer limits of the alto saxophone.