These days Howard Levy spends precious little time with his hometown friends; that's the price you pay for cofounding and touring with a popular Warner Brothers band like Bela Fleck and the Flecktones, in which Levy's keyboard and harmonica work constitute two of the three lead voices. At this concert Levy will stick almost entirely to harmonica--a nod to the fact that, at this point, his wild-ride harp solos have all but eclipsed his exuberant, thoroughbred piano playing. From the strict standpoint of instrumental technique, Levy's accomplishment on the lowly blues harp resembles those of such jazz artists as Milt Jackson on vibraphone and John Coltrane on the soprano sax: he has created a style that makes people hear the instrument in a new way. Other jazz harmonicats use a chromatic harmonica, which, along with a refined tone, boasts all the "in-between" notes that the typical little Marine Band harmonica lacks. But two decades ago Levy discovered he could bend the notes of this ordinary blues harp up--or sharp--as well as down (which was all that any of us had ever heard before). His relentless perfection of this invention now allows him to play complicated bebop lines and even free jazz with the facility of a pianist's right hand, while retaining the gritty, wailing street sound of the blues harp. Pianist John Weber will anchor the quartet, and you can count on cameo appearances from several well-known Levy associates to spice the mix. Sunday, 2 PM, Unitarian Church of Evanston, 1330 Ridge, Evanston; 477-7738.