Mogwai

At Mogwai shows, sound waves visibly distort the air, like summer heat warping the horizon. Even if fans cranked the volume on a recording of one of the band's sets while clamping high-end headphones to their ears, they could not duplicate the experience. Recognizing that a standard live record wouldn't work, the group has released Government Commission, culled from seven years of sessions with the BBC's Steve Lamacq and John Peel. Though it's plenty loud at times, it functions like an unplugged album, revealing all the spontaneous shifts that usually get swallowed in sonic blasts.

Whether on air or in the studio, Mogwai takes its time building instrumental momentum. For five and a half songs, guitar lines hover, dangle and linger; distant drums tap like knocks at a neighbor's door; vocals haunt and hide; and bass lines simmer like an idling engine. Suddenly, the guitars squawk like exotic birds under attack, catalyzing a chaotic climax. The album never again approaches that intensity, nor does it need to. Having bottled its concert-hall cacophony, Mogwai returns to rhythms that rise and fall with respiratory regularity.