Robert Plant and Alison Krauss' Raising Sand is touted as a bluegrass album, but the collaboration between erstwhile rock god Plant and onetime fiddle-prodigy Krauss has as much to do with Bill Monroe's kind of music as Lil Wayne's new CD. If anything, Raising Sand is an atmospheric take on Delta blues, filtered through producer T Bone Burnett's arty haze. It's a record of transplanted Americana, as seen through the eyes of Brit Plant and Nashville insurgent Krauss. Plant suppresses his Zeppelin shrieks to get closer to Krauss' tuneful sighs, and at times, their gorgeous harmonies approach a sort of spiritual relief. Things barely move beyond a whisper (a muddy rockabilly cover of the Everly Brothers' "Gone Gone Gone" is an exception), but the moody melancholia immaculately fits this endearingly odd couple.