When Richard Davis began playing jazz in his hometown in the 1950s, he changed the face of Chicago bass playing. Before Davis, such bass players as Milt Hinton, Truck Parham, and Wilbur Ware had crafted a style distinguished by earthy timbre and uncomplicated swing: they played the bass as if it were an extension of the ground they stood on. But Davis, encouraged by the legendary teacher Captain Walter Dyett, extended his expertise to classical music (and in fact has free-lanced with prestigious symphony orchestras throughout his career). From that world he brought a lighter, more focused tone, a rather variable approach to the beat, and a cache of innovative techniques and improvisational concepts. Davis's style became the basis for a "second school" of Chicago bassists, one that includes such successors as Rufus Reid, Steve Laspina, and Larry Gray. In the 60s Davis moved to New York, where he came to represent the "new wave" of versatile, college-educated jazzmen--one night performing with Leonard Bernstein, the next anchoring the Thad Jones-Mel Lewis Orchestra. Some of us feel that especially since he moved to Madison to teach, Davis's jazz work has lacked the sincere emotionalism his repertoire demands; but no one disputes his ranking among the great virtuosi of the bass. Davis heads a New York-based quintet that nevertheless boasts a strong midwestern flavor. It features Detroit native Sir Roland Hanna, whose own classically grounded style shapes some of the most nourishing solos in jazz; the steely trumpeter Cecil Bridgewater (born, bred, and educated in Urbana, where he made his name while attending U of I in the 60s); and the unimpeachable drummer Marvin "Smitty" Smith, who comes from Waukegan. (The band also includes the schooled yet excitable tenor Ricky Ford; he grew up in Boston, but don't hold that against him.) Saturday, 9:30 PM, HotHouse, 1565 N. Milwaukee; 235-2334.