If you go to the theater you know Michael Roth's music, for not a season goes by in Southern California when he does not provide the scores for a wide array of stage productions. The La Jolla Playhouse and Costa Mesa's South Coast Rep are two theaters where Roth's musical inventiveness deepens the stage action, creates mood, underlines dramatic emotion, and makes its statement of form and meaning. Roth can give plays everything from classical to pop, with every imaginable tradition of musical thought. At the same time, he has his own distinct voice, so that every Roth theatrical score is recognizably his. He is a great writer of tunes, a master of expressive harmony, and a connoisseur of instrumental colors and textures. He is especially terrific at devising songs that sit well for the voice and stick in the memory. Next time you go to a play with a Roth score, pay closer attention to the music, and you may be surprised how rewarding it can be just on its own.