This group has only played a couple concerts over the past two years, but its roots stretch all the way back to 1990, when Buenos Aires-born clarinet and saxophone player Guillermo Gregorio first encountered German trumpeter Axel Dorner in Thomas Lehn’s jazz ensemble. During the hours of impromptu duets they played in each other’s apartments, they discovered a shared talent for improvising with the subtlety of chamber musicians. The quartet, convened by local bassist Josh Abrams for a February 2000 concert at Lula Cafe, amplifies that dynamic; its free play sounds as deliberate as Gregorio’s and Abrams’s compositions, and a cool demeanor governs its microtonally shaded melodies and gently swinging rhythms. Dorner is in town to play with Ken Vandermark’s Territory Band as part of the World Music Festival later this month, but he’ll start his run here with these concerts, which are a warm-up for a recording date for an as yet unidentified label. Tuesday, September 10, 9 PM, Hungry Brain, 2319 W. Belmont; 773-935-2118. Wednesday, September 11, 8 PM, Empty Bottle, 1035 N. Western; 773-276-3600.

Art accompanying story in printed newspaper (not available in this archive): photos/Michael Jackson.