Government Commissions: BBC Sessions 1996-2003 (Matador)

At Mogwai shows, sound waves visibly distort the air, like summer heat warping the horizon. Even if fans cranked the volume on a perfectly produced recording of one of the band's sets while clamping high-end headphones to their ears, they could not come close to duplicating the experience.

Recognizing that a standard live record wouldn't work, the group opted to release Government Commission, culled from seven years of sessions with the BBC's Steve Lamacq and John Peel. This collection captures Mogwai's improvisational flair and gorgeous glacial dynamics. Though it's still plenty loud at times, it functions as an unplugged album, revealing all the subtle spontaneous shifts that usually get swallowed in sonic blasts.

Whether on air or in the studio, the band takes its time to build 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, everything explodes. The guitars crackle during the initial climax, then start squawking like exotic birds under attack. A few aftershocks follow the first seismic outburst, and finally, at the 15-minute mark, Mogwai caps the composition with complete chaos. 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.