Using “texture” is old hat in free improv, but the music on Heat Transfer (For 4 Ears), the second and most recent album by the trio of violinist Hans Burgener, cellist Martin Schutz, and bassist Barre Phillips, is practically sculptural. The musicians, who’ve cumulatively covered a lot of stylistic territory–Phillips played with an orchestra on Ornette Coleman’s Naked Lunch sound track, Schutz has been known to radically alter his sound with electronics, and Burgener has scored dance pieces–make creative use of their bows, laying down slippery, dissonant layers of dark tones. But they often sound like they’d rather be drumming, punishing their instruments with pizzicato thwacks and slapping and tapping their wooden bodies. The music is markedly dynamic, with constant shifts in density and intensity: a serene passage of something resembling classical chamber music morphs into upper-register chalkboard scrapes, which in turn dissolve into low, spooky, and spacious legato moans, which are exploded by a burst of snaps, crackles, and pops. The music is in constant flux, but it never falters: these guys are excellent listeners, able to instantly isolate and build upon microscopic kernels of sound. This is the trio’s Chicago debut. Wednesday, June 11, 10 PM, Empty Bottle, 1035 N. Western; 773-276-3600.