We’re long accustomed to seeing African-American musicians perform for audiences that are 80 percent white, but the reverse is still pretty unusual — and it was especially unusual, if not outlawed, in the segregated South of the 1950s. This is the setting of Memphis, the Tony-winning Broadway musical set in the titular Tennessee city, whose blues and proto-rock ’n’ roll, originated by blacks, sounded positively lascivious compared with the white-bread country emerging from Nashville. The musical charts the travails of the only white DJ in Memphis as he falls in forbidden love with an electrifying black singer. Puncturing racism with rhythm, Memphis is more roof-raising rock revelry than didactic morality tale, which sounds pretty perfect. David Bryan, a founding member of Bon Jovi, wrote the score, but don’t hold that against it. The talented behind-the-scenes crew worked on acclaimed New York productions such as Xanadu, The Toxic Avenger, and The Drowsy Chaperone.