Few younger-generation blues outfits can fuse reverence for the music with an ass-kicking sense of fun like the T-Birds do. They seem to have mastered every conceivable regional style, from jumping roadhouse romps to hard-grinding Chicago boogie all the way to the crunching, rock and roll-flavored young man's blues that Albert Collins and his contemporaries forged in Texas in the 50s and early 60s. The nucleus of the group is harmonica wizard Kim Wilson: he's not only mastered the style of the masters, but he seems to have absorbed their souls as well. As he segues through generations of genius with his sweet-souled tone and impeccable technique, he sometimes seems possessed: he'll hunch over and snap his fingers in front of his face like Sonny Boy no. 2, then suddenly with a stylistic shift extend one palm upward like Big Walter, and finally culminate with a James Cotton-like blast that finds him jumping up and down in circles like Cotton himself. But his playing is no mere imitation: through it all Wilson puts his own spin on it, throwing in creative little asides and notes, always keeping it tasteful no matter how fast and furious his improvisations. Saturday, Buddy Guy's Legends, 754 S. Wabash; 427-0333 or 427-1190.