A shambling wreck of an album, Big Star’s Third/Sister Lovers ranks among the most harrowing experiences in pop music; impassioned, erratic, and stark, it’s the slow, sinking sound of a band falling apart. Recorded with their label, Stax, poised on the verge of bankruptcy, the album finds Alex Chilton at the end of his rope, sabotaging his own music long before it can ever reach the wrecking crew of poor distribution, indifferent marketing, and disinterested pop radio. His songs are haphazardly brilliant, a head-on collision between inspiration and frustration, and the album is a kind of self-fulfilling prophecy, each song smacking of utter defeat and desperation. The result is either one of the most vividly emotional experiences in pop music or a completely wasted opportunity. While the truth probably lies somewhere in between, there’s no denying Third’s magnetic pull — it’s like an undertow.