It isn’t often you get to be the music director for a work of theater that, well, isn’t a musical. “I’ve never done anything like this,” says Justin Craig, the New York City-based music director for the acclaimed play “Stereophonic,” on the phone recently from Los Angeles. “I don’t think anything exists like this.” The most Tony Award-nominated play of all time and the winner of five Tonys, including Best Play, “Stereophonic” is about to begin a three-week run in Cleveland as part of Playhouse Square’s 2025-26 KeyBank Broadway Series. The idea that “Stereophonic” isn’t a musical is technically correct but also could be misleading. It is built around a fictional rock band recording an album...