The Norwegian improv quartet Supersilent doesn’t give you much to go on. Its albums and songs have numbers for titles (the lead track on 4, for instance, is “4.1”), and the CD packaging for the last two releases (5 and 6, both on Rune Grammophon) omits any kind of ornament as well as the players’ names, providing only recording information. (As member Helge Sten, aka Deathprod, told the Wire last year, “Each piece may generate personal images for each listener.”) All you get is the music, and though it’s not entirely without antecedents–early-70s Miles Davis electric jams, the polyethnic ambient work of Jon Hassell–it doesn’t really sound like anything else out there. Arve Henriksen (trumpet), Jarle Vespestad (drums), and Stale Storlokken (keyboards) are conservatory-trained musicians and active members of the Scandinavian jazz scene, with numerous credits for ECM, and they’ve played together for years as a free-improv trio called Veslefrekk. But their approach gets a lot trickier when they’re joined by Sten, an engineer and real-time electronic manipulator who describes his role as that of “audio virus.” All of Supersilent’s music is improvised and the players say they never rehearse together, yet the music moves with a precise focus and coherence, constantly morphing, never settling into fixed patterns. Henriksen’s trumpet lines–sometimes acoustic, sometimes treated with effects–flow like mercury through the electronic mazes built by Storlokken and Sten, while Vespestad shifts gears from fractured grooves to pin-drop colorization to explosive chaos. This is the group’s Chicago debut, and one of only three U.S. performances on the current tour. Tiny Hairs open. Saturday 11/6, 10 PM, Open End Gallery, 2000 W. Fulton, 773-276-3600 or 800-594-8499, $12. All ages.