The Kronos Quartet, who made an auspicious local debut two seasons ago, are back for a three-recital "Festival of New Music," sponsored by the forward-looking Chamber Music Chicago. New-wave affectations aside, the Bay Area-based foursome are unquestionably among the best interpreters of 20th-century repertory, often the equal of the Juilliard Quartet in their intensity and probing intelligence and more venturesome than any other classically trained group I can think of. Their growing popularity, ironically perhaps, is due partly to their visual presentation--the color-coordinated space-age costumes and ultrahip mannerisms--which strikes a responsive chord among younger audiences more attuned to the Talking Heads. This gambit has paid off handsomely, making the Kronos a crossover phenomenon that bridges the generation gap and enabling them to present (and commission) fascinating, experimental pieces that enrich a previously moribund genre. Characteristically, the Kronos's opening program holds three local premieres: the Third String Quartet by Alfred Schnittke, who is the most important of the contemporary Soviet composers; White Man Sleeps by Kevin Volans; and Mary Ellen Childs's Four of One of Another. Also included are a pair of slightly older "classics": Bartok's Fourth Quartet (1928) and Morton Feldman's Structures ( 1951), noted for its graphic notations and subtle variations in aural densities and timbres. The guest soloist is accordionist Guy Klucevsek. Monday, 8 PM, Royal-George Theatre, 1641 N. Halsted; 242-0237 or 663-1628.