The 22-year-old Canadian string chamber orchestra has produced dozens of highly enjoyable discs, including many award-winners. But hearing them play an all-Russian program live at Oberlin College Sunday night was even better. No digital medium yet developed can convey the sense of individual and collective accomplishment these 15 players exude under their founding director, Yuli Turovsky. Only in person can one fully appreciate their musical discipline and their responsiveness. Tchaikovsky was the first to receive their attention Sunday night. Standing in a wide semicircle onstage at Finney Chapel, they presented his Andante Cantabile and the Serenade for Strings. Turovsky kept the players on a tight leash in the Andante, and they hewed closely to his wishes in a performance of exceptional delicacy and restraint. Dynamic and metrical subtleties abounded even as the overall warmth increased by barely perceptible degrees. Bolder strokes, greater urgency and richer tonal sheen marked much of the Serenade. Their account of the waltz included an unusually large number of swaying surprises, and the finale nearly approached dramatic excess. The Nocturne from Borodin`s Second String Quartet appears on most programs of Russian music, and theirs was no exception. Their actual performance, however, most certainly stood out. Remarkably cohesive in ensemble terms and brightly shimmering, it held listeners on emotional tenterhooks. Displayed behind I Musici de Montreal were large paintings by Natasha Turovsky, the director`s daughter and a violinist in the group. But distractions they were not. Rather, they were imaginative illustrations for the final musical work, Mussorgsky`s beloved "Pictures at an Exhibition." The elder Turovsky made a creative contribution, too, in the form of expressive and highly inventive arrangements ("Pictures" was originally a suite for solo piano) that placed the strings in fresh combinations for each "Promenade." The "Bydlo" scene was the most distinguished of this musical gallery. Turovsky`s bleak painting of a wooden oxcart carrying bodies was the exact visual equivalent of a morose and plodding performance that faded away on a single tone like a foghorn offshore. Of the four works on the program Sunday, Mussorgsky`s "Pictures" is the one I Musici de Montreal haven`t recorded. A disc wouldn`t capture their performance completely, but it would make a lot of listeners happy. Cleveland