Grace Slick was the female face of psych rock. But she wasn't Jefferson Airplane's original frontwoman. This concert disc (one of four newly released shows) is the first official live album to feature Signe Anderson, whose style is more folk-blues mama than icy acid queen. Anderson belts out songs like "Chauffeur Blues," and elsewhere the Airplane reach cruising altitude on a nine-minute improvisation driven by throbbing bass lines.

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“I'm Yours”

Jason Mraz re-emerged after his disappointing second album with this lead single, a Jack Johnson-esque ditty about giving yourself fully to someone else. The success of the reggae-tinged song (it earned two Grammy nods and a spot on the Billboard singles chart for well over a year) was something the folk-pop singer never predicted when he wrote it in 15 minutes at home. "I played a happy-hippie chord progression that would probably work without 50 different Bob Marley songs," he told Rolling Stone. "I thought, 'It's too novelty. This is a nursery rhyme,'" concluding that "you can never guess what's gonna be a hit."