It’s only a sextet, but don’t tell Les DeMerle–he thinks he’s leading a big band, and that belief dominates his approach to the drums. He drives the up tunes with a large, blunt, explosive kit sound; when the music requires nothing more than a steady beat, he employs the sharp cymbal sting that’s traditionally used to cut through an orchestra three times the size of the Transfusion. And even though DeMerle carries only three horns, the arrangements punch and jab as if they started life as flashy big-band charts before going under the knife and getting cut down to size. Sometimes that leads to a certain boxiness in the sound; more often, it generates a lot of power, and serves as a launch pad for Nick Drozdoff (trumpet), Bob Fredricks (tenor), and John Kaplan (alto, soprano, and flute). These guys aren’t high-priced soloists: they just play that way. And DeMerle–a prodigy who at the age of 16 held the drum chair in Lionel Hampton’s band–exhibits a technical mastery that will remind you a little of Buddy Rich. The Transfusion’s still finding its stride, but it has the makings of a crackerjack mainstream unit. Wednesdays through Saturdays, Nick’s Fishmarket Lounge, 10275 W. Higgins, Rosemont; 298-8200. Sundays, Jorge’s Restaurant y Cantina, 1161 N. Dearborn; 787-5050.