In the wave of free improvisation and hyper-expressionism that characterized the avant-garde of the 60s and 70s, the most important players were pianists and reedmen; for some reason, the trumpet players have gotten scarce, and finding two such worthy practitioners in one weekend series makes for a rare treat. Leo Smith, a member of Chicago’s Association for the Advancement of Creative Musicians (AACM), has impressive credentials–he took part in the AACM’s first official New York concert, in 1971–and musicality to match. He is among the most abstract, and yet at the same time cogent, performers and composers of new music; tonight, his compact strokes and broad sweep will be joined by the towering virtuosity of reedman Douglas Ewart and the panrhythmic pulse of drummer Hamid Drake. Saturday brings the trio led by trumpeter Paul Smoker, making (I believe) their much-anticipated Chicago debut. Smoker, who teaches music at Coe College in Iowa, is a wonder, offering a style that boasts traditional trumpet virtues–a full but malleable sound, along with a powerful, swaggering swing–and an insatiable need for venturesome experimentation. His trio, featuring his former students Ron Rohovit on bass and Phil Haynes on drums, breathe this demanding music at a level of superconsciousness; they’re tighter than spandex. Tonight (Leo Smith) and Saturday (Paul Smoker), 8 PM, Ferguson Theatre at Columbia College, 600 S. Michigan; 283-0531. (A “series admission” is available for the two concerts.)