Rock Rolls With Bluegrass

He's a howling rock god; she's a fiddlin' bluegrass queen. It sounds like an odd pairing, but Robert Plant and Alison Krauss weave haunting harmonies on tour, reports Rolling Stone. The duo admits they struggled to find the right groove while performing Led Zep covers and R&B classics from their 2007 platinum collaboration, Raising Sand.

Krauss kept an ear trained for Plant's improvisations while Plant adjusted to sharing the mike. "I'm listening intently up there, because I've never heard another singer alongside me," he says. "And white mountain music—it's new to me." The blending of styles works because, in the words of Sand producer T Bone Burnett, "they're both soulmen." (More Rolling Stone stories.)