Broken Bells' Pop-Savvy Return

The electric second record ups the ante for adventurous, pop-savvy rock

When new acquaintances ask Brian Joseph Burton what he does for a living, he skips the title of producer, omitting that he's masterminded records by Norah Jones, the Black Keys and, soon, U2. He doesn't refer to himself as a DJ, either, despite having put out what some call the best remix record ever (his unauthorized mashup of Jay-Z and the Beatles on 2004's The Grey Album). He doesn't even mention his role in Gnarls Barkley, the duo responsible for the neo-soul song "Crazy," one of the most successful singles of the past decade. No, Burton, a.k.a. Danger Mouse, gives a...