Like many musicians of his age, Bon Iver’s Justin Vernon isn't content with working solely on his day job; he spends just as much time on his side project. In Vernon’s case it’s with members of the post-rock groups All Tiny Creatures and Collection of Colonies of Bees. They come together as Volcano Choir, and the group's second album, Repave, shows discipline and intensity only hinted at on its casual debut, Unmap. “Alaskans” mutates from sounding like a lovelorn Barry White into a self-referential minor rock star during a spacey, acoustic ballad where the instrumentation appears to loop around a few piano and guitar riffs until it floats away. “Dancepack” sounds like the group decoding its own version of The Arcade Fire and its visions of grandiosity. Modern arena rock sounds pop up throughout, and Vernon’s singing veers from mock falsettos (“Keel”) to whiny, soul-demanding shouts and serious, spoken moments. Unlike arena rock bands of previous generations, there are no choruses that demand the spotlight and no rousing beats to organize the troops. This is art-rock for the experimental crowd.