In the 1950s experimental composer Christian Wolff was part of the New York scene that included John Cage, Earle Brown, and Morton Feldman. Cage in fact provided Wolff with his only formal instruction in composition, and Feldman was to become his lifelong friend; both men’s influence can be heard in his work to this day. Wolff often does without key signature or meter, or omits the clef so that a line can be read in any register; sometimes he casts off traditional notation entirely, relying on symbols that require the performers to invent meanings on the fly. In the late 60s and early 70s Wolff became involved in the antiwar and civil rights movements, and began incorporating politicized folk songs into his work (“Peggy,” for instance, quotes tunes Peggy Seeger wrote or sang). But in a sense his music has always been political. In accord with his egalitarian principles, Wolff has relinquished some of a composer’s authority: performers are given the freedom to determine a work’s structure or instrumentation (such as in “Music for 1, 2, or 3 People,” from 1964), and within a piece they can often reshape the loose score by signaling each other musically. In general his work is sparse and quiet, written for small groups rather than orchestras; though Wolff frequently uses indeterminacy–which can make the performers seem like gears in a randomizing machine–his music is usually organic and intensely expressive. The Maverick Ensemble, a relatively new local organization that combines music with art and video, has chosen Wolff as the featured composer for its second annual festival, which opens Wednesday at HotHouse and then runs June 13 through 16 at the University of Illinois at Urbana-Champaign. Maverick’s core members are Paul Oehlers (electronics), Joan Marie Dauber (voice), and William Raynovich (cello), but only Raynovich will be among the ten musicians performing here (the roster also includes percussionist Steve Butters and flutist Lisa Goethe-McGinn). “Music for 1, 2, or 3 People” is on the bill, as are “Pairs,” another key Wolff composition from the 60s, and 1977’s “Dark as a Dungeon.” Anton Webern, a major influence on Wolff, will be represented by his Three Little Pieces for cello and piano; also on the program is Raynovich’s “Vc Pc,” inspired by the Webern. Wolff will be present at the concert. Wednesday, June 12, 6 PM, HotHouse, 31 E. Balbo; 312-362-9707.