Few bands changed their sounds as dramatically as Pink Floyd, whose rotating leadership, penchant for the bizarre and nearly unmatched virtuosity led to new colors every time they entered the studio. Animals, released in 1977, sometimes gets lost in the shuffle -- eschewed by fans of early psychedelic starkness and avoided by those prefer warm and polished albums like Dark Side of the Moon.

It preceded The Wall, a concept double-album, but in many ways it's far darker. The Wall discusses the pain of isolation, but Animals sees no redeeming value in anyone. The Wall discusses misogyny, but Animals thinks everyone is to blame. People are dogs. Or pigs. Or sheep. Even the cover art -- a pig floating above an industrial wasteland -- was cold to the touch.

Still, the music is some of the finest Floyd ever made: consistent in theme, tightly played and engaging even when the band is actively trying to rebuke its listeners. "Pigs (Three Different Ones)" is the standout track, with great riffs from all parties that combine into a sustained assault.