Louie Bellson, who turns 70 on Sunday, brings a suave demeanor and relaxed elegance to his drumming; such qualities could obscure the fact that he brought a flamboyant novelty to the big bands of Basie and Goodman were it not for the electrifying energy that still characterizes his playing. (When Bellson fully came into his own, as the drummer and an occasional composer for Duke Ellington's band in the early 50s, Buddy Rich held sway as jazz's most technically proficient percussionist. Bellson could play anything Buddy could; he just did it with taste.) Bellson was the first to use two bass drums in his trap set, and he still articulates both of those cumbersome instruments with deceptive ease, making them sound almost as crisp as the piercing dance he performs on the ride cymbal. His unfailing exactitude goes hand in hand with a high level of creativity, making it no wonder he can attract such high-powered sidemen as trumpeter Marvin Stamm--another musician whose unforced virtuosity elicits murmured assents among musicians--and saxophonist Ted Nash, whose especially focused solos carve their own niche in familiar material. For this engagement, pianist Larry Novak and bassist Larry Gray complete the rhythm section, giving Bellson the latitude to do anything he chooses. Bellson is one of the very few drummers who make it worth your while to sit near the drums: his precision-tuned control ensures that he won't overpower the other instruments, and watching the deft accents he plays with unfailing musicality, you see how every stroke can not only drive but also shape the music at hand. Friday through Sunday, Joe Segal's Jazz Showcase, Blackstone Hotel, 636 S. Michigan; 427-4846.