Plenty of orchestras can deliver fine performances, but too few take an intelligent, purposeful approach to programming. The Chicago Symphony Orchestra, for example, is notoriously lackadaisical in this department, often slapping unrelated pieces together at the whim of a conductor. Concertante di Chicago, on the other hand, prides itself on grouping works that shed light on a certain style, period, or trend. Its willingness to inform, rather than merely entertain, has garnered this first-rate conductorless chamber ensemble an appreciative following. For its new season Concertante’s guiding force and founder Hilel Kagans has scheduled a jazz-classical crossover show, a revival of Richard Strauss rarities, and a survey of Hungarian folk-inspired music. The season opener is entitled “Neoclassical Portraits,” takes a look at three modern composers’ attempts in the 1920s and 30s at updating and reinterpreting classisism. Stravinsky’s evocative ballet suite Apollo Musagetes relies on iambic rhythms in a seemingly stream-of-consciousness reflection on the unity of the arts. Variations on a Theme of Frank Ridge is Britten’s thoroughly British addiction to a venerable tradition. Martinu’s Concerto da Camera as the title suggests, is cast in the mold of the Baroque concerto grosso but contains unmistakably dissonant touches Ruben Gonzalez, one of the CSO’s two concertmasters, solos in the Martinu. Thursday, 8 PM, Cove Auditorium, 520 Glendale, Winnetka. Sunday, 3PM, concert hall, DePaul University, 800 W. Belden; 454-3010.