When Lambchop were first conceived as Posterchild in the late '80s, it was in the spirit of getting together to play with no discernible purpose. Anybody who wanted in could have in. There is still something of that spirit in the 11-piece edition of Kurt Wagner's venerable Lambchop that appeared at Merge Records' 20th anniversary festival in North Carolina in July 2009. Between horns and keyboards and multiple strummers, including the supremely tasteful lead guitarist William Tyler -- who embodies Lambchop's indie Nashville vibe to a T -- Wagner's project is still impossible to classify, and completely sublime. Wagner pulls from all corners of his 15-year career, stacking them into a pleasing arc, including erudite mid-set R&B ("Your Fucking Sunny Day," from 1997's Thriller), a show-opening alt-country lilt ("I Will Drive Slowly," from 1994's I Hope You're Sitting Down), and a joyous rock climax ("Give It," which begins as a half-sung recitation and propels itself into a chorus of Talking Heads' "Once in a Lifetime"). Recorded pristinely, the band's first official live album -- not counting a few tour-only discs -- is as pleasing as any of its ten albums, the wall of sound as fresh and wonderful as ever. On "Grumpus," from 2000's Nixon, the band fits together brass, noisy guitar, Tyler's reverberated fingerpicking, and slightly dirty synth fills, each totally finding its own space in the mix. Complex and accessible, avant-garde and pleasing to the ear, introspective and cathartic, Lambchop communicate themselves in full, and there remains nobody like them in American music.