''Brilliant and epoch-making.'' Times Literary SupplementThe Classical Style is an established classic which has remained in print since its first publication in 1971. With his experience as a world-class pianist as well as as teacher at Harvard and Oxford, Charles Rosen produced the definitive survey of the language of the music of the classical period. In the book, Rosen concentrates on the three major figures of the time - Haydn, Mozart and Beethoven - because ''it is in terms of their achievements that the musical vernacular can best be defined''.In this expanded edition, Rosen follows the development of each composer''s best known genres: for Haydn, the symphony and string quartet; for Mozart, the concerto, string quintet and comic opera; for Beethoven, the piano sonata. In addition, the author ranges widely through the material of classical music which falls outside these categories. ''The word "masterpiece" should be used rarely if at all. But it applies to The Classical Style . . . this book sets new standards for the application of language to music.'' George Steiner