Rick Rubin and rapper Jay-Z in 2004
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As always, he has no shortage of work, with albums by Kanye West, Metallica and Linkin Park in various stages of readiness, but the project that's closest to his heart is a sixth and final album from his recordings with Johnny Cash. Settling onto his couch, Rubin plays a Cash version of Redemption Day, an overlooked song from a 1996 Sheryl Crow album. "Johnny found this," he says. "I'd never heard it, but it's perfect for him." Rubin was worried that he might have to tinker more than usual with some of the songs in the singer's absence, but after listening to the material again, he decided he was wrong. "I don't think I'll need to do too much. I mean, how much can I really improve Johnny Cash?"