On his first solo album, Black Keys guitarist Dan Auerbach leaves behind the electric blues sludge of his main band and flirts with Sixties British folk and Delta balladry. "Real Desire" echoes Tommy James and the Shondells' "Crimson and Clover," complete with droning bass and billowing organs. On "Heartbroken, In Disrepair," Auerbach sounds like Robert Johnson at the crossroads: "God may forgive me, but that's not enough," he croons. Keep It Hid lacks the brutish force of the Keys' stuff, but it makes up for it with variety.