Mark Dresser and Denman Maroney have played together in lots of groups, including the quartet Tambastics, Dresser's quintet Force Green, and a trio with Dave Douglas, but it all started in 1989 with an improvised duo gig. It's a setting that spotlights the depth of their interaction and their like-minded physicality. Maroney, a pianist, spends a lot of time under the hood, one hand on the keys, the other manipulating the strings using some foreign object; he might slide a bowl up a string for bluesy inflections, depress another at a node for a ringing harmonic, or drape something over several at a time for buzzy prepared-piano effects. Of course Henry Cowell, John Cage, and umpteen adult and child pianists have gone a-hunting under there too, rediscovering piano as both a percussion and stringed instrument, and in truth Maroney's not the most adept practitioner of what he grandly calls "hyperpiano" (Cor Fuhler cuts him, for one). But he's more single-minded about it than most. He can get around on the keys, too: his rapid flurries may conjure Conlon Nancarrow's whacked-out player-piano music. Dresser, tied with William Parker as downtown New York's most-sought bassist, is a master of forceful attack, room-rattling timbre, bow scrapes and conspicuous slides; his trademark lick is a burst of hand-over-hand swoops up one string: wow wow wow wow. His dark percussive sound is a good match for the pianist's on their improvised Duologues (Les Disques Victo), recorded a year and a day before this appearance, which will combine improvisation and composition. Together they can phrase with a drummer's crack timing, grind like machinery, or create chilly atmosphere. But there are moments of puckish charm, too, as if each got swept up in the pleasure of playing with someone who really understands. Monday, November 5, 7 PM, Storefront Theater, Gallery 37 Center for the Arts, 66 E. Randolph; 312-742-8497.