Octahedron by The Mars Volta

Two things are pretty much a given with any new Mars Volta album: 1) You will have no idea what to expect going in, and 2) It will be at least great if not phenomenal. Octahedron by The Mars Volta ($10), the group's fifth studio album, is no exception, mostly eschewing the more manic, heavier sound of their last two efforts for a stronger acoustic tinge, and offering up some of Cedric Bixler-Zavala's most heartfelt lyrics yet. [Thanks, RG]