When Will Butler left his band Arcade Fire, he didn’t know what would happen next. With a Grammy on his shelf and an Oscar nomination for his musical score on Spike Jonze’s “Her,” it seemed like he could do anything — why not Broadway? Now, he’s written and composed the music for “Stereophonic,” a new play that was recently nominated for a record-breaking 13 Tony Awards. Set in the 1970s, it follows a fictional rock band on the cusp of superstardom as they struggle through recording their new album. Will talks to Tom about which moments from the play felt like he was dipping into his own past, how a band’s relationships influence their art, and why it was good he didn’t know anything about ‘70s rock music.