Thirty-nine years ago trombonist Paul Rutherford wrote a pair of sprightly, ingratiating free-jazz themes for Challenge (reissued in 2001 by Emanem), the first album by the Spontaneous Music Ensemble. The title of one of those tunes, "2.B.Ornette," tells you exactly where he was coming from at the time, but he soon abandoned both composition and the jazz idiom. Iskra 1903, his early-70s trio with Derek Bailey and Barry Guy, was one of the first groups he used to cut ties with convention; on his landmark 1974 solo debut, The Gentle Harm of the Bourgeoisie, he sounds truly liberated, his trombone speaking in hitherto unknown tongues. Rutherford augmented his adroit manipulation of slide and mute with multiphonics, simultaneously singing through and playing the horn to get effects ranging from high-pitched quivers to low, guttural blasts. But though his playing is highly abstract and unpredictable, the 65-year-old Londoner hasn't lost his knack for coming up with a good tune. Trombolenium, a 2002 collection of solo improvisations, is full of them; "Stalf" is deliberate and pensive, while "Second China Pig Extract" is voluptuous and downright comedic. His melodies even stand up to the hall-of-mirrors refractions that computer musicians Robert Jarvis and Lawrence Casserly create on Iskra3 (Psi). Tonight Rutherford plays in a quartet with Peter Brotzmann, Kent Kessler, and Nasheet Waits and in the group Hoxha with Ken Vandermark, Torsten Muller, and Dylan Van Der Schyff. On Saturday Rutherford plays in a duo with drummer Robert Barry at the Empty Bottle; see the Critic's Choice on Sam Rivers and the Fred Lonberg-Holm Trio. Fri 6/17, 9:30 PM, Empty Bottle, 1035 N. Western, 773-276-3600 or 800-594-8499, $15.