What is the secret to making a hit song? In Let’s Go Crazy: Prince and the Making of Purple Rain, Alan Light, a former writer at Rolling Stone, looks at how Prince’s song, album, and movie became a musical juggernaut since audiences first heard the song in 1984. Walter Holland’s Phish’s A Live One examines the cultural context for the band’s groundbreaking 1995 album. And John Seabrook, in The Song Machine: Inside the Hit Factory, takes you into the world of hooks and computerized composition. From the jam band to the pop machine, this session considers how music moves and manipulates us. Get a virtual-lighter app for your phone and be ready to cheer. Moderated by the music-loving host of WBUR’s On Point, Tom Ashbrook.