On Object 3, the latest in the local Locust Music label’s “Object Series,” tenor saxophonist Matt Bauder and bassist Jason Ajemian venture into a hall of mirrors. The album-length piece “Normal” begins as a composition of wavering long tones in which not a lot really happens. Bauder’s sound is beautifully striated and bathed in shadows, and his intonation is meticulous: the sustained notes rise and fall slowly and precisely. Bowed lines from Ajemian, ranging from low-end rumbles to upper-register swirls, combine with the saxophone in glacial, funereal harmonies. Here and there one player drops out, leaving space for a gentle solo. They proceed this way for about 15 minutes–and then they enter the fun house. Randomly sampled snippets from the performance thus far begin to play back in real time, forcing Bauder and Ajemian to adapt. They don’t stray too far from the long-tone approach, but their harmonic choices clear out room for the jumble of cut-up sounds, and the music gains in density and movement. At the Empty Bottle on Tuesday they’ll repeat the process, with new samples taken from the piece as it’s played. Ajemian is very active in the local improvised-music scene, but Bauder has been attending grad school at Wesleyan for the last two years and hasn’t performed much; he’ll soon be moving to Karlsruhe, Germany, to study electronic music at ZKM, so his local gigs won’t get any more frequent. He’s appearing Wednesday at the Bottle with the Scott Rosenberg Big Band, and the next night he and Ajemian will lead their band at 3030. Tuesday, August 12 (Bauder and Ajemian), and Wednesday, August 13 (Bauder with Rosenberg), 9:30 PM, Empty Bottle, 1035 N. Western; 773-276-3600. Thursday, August 14, 9:30 PM, 3030, 3030 W. Cortland; 773-862-3616.