New Yorker John Corigliano is perhaps one of the most important figures on the local music scene: as the Chicago Symphony's composer-in-residence for the next two years, his mission is to promote new music and to serve as a conduit between the creative community and the venerable institution that has long ignored it. Thus, for those among us who are not acquainted with Corigliano's ouevre, this William Ferris Chorale retrospective, in celebration of his 50th birthday, provides a timely introduction. Corigliano calls himself a "theatrical, journeyman" composer, by which he means that instead of belonging to any stylistic orthodoxy he draws from a wide repertory of idioms to write music for particular occasions or specific performers. And, to keep audiences entertained, he often uses unusual instrumentation and even nontraditional seating arrangements. Indeed, some of his best compositions, such as the Oscar-nominated score for Altered States and the Clarinet Concerto, were made to order and have remained popular. This accessibility and eclecticism has provoked envy and dismissal from some quarters but prompted Aaron Copland to remark that "John is the new me." Though lacking stylistic trademarks, Corigliano's music does recall Copland's lyricism and Bernstein's orchestral glitter: it is evocative, plaintive, sustained by a nervous, irrepressible energy. Among the highlights in this Ferris Chorale sampler are: the sardonic tone poem A Black November Turkey, the forlorn Poem in October, and the dramatic Aria for Oboe and String Quintet. Tonight, 8 PM, Our Lady of Mount Carmel Church, 690 W. Belmont; 922-2070.