Raise the Roof by Robert Plant & Alison Krauss [7/10]

A decade and a half after Raising Sand, a seemingly unlikely but wonderfully realized collaboration of covers by metal idol Robert Plant and bluegrass-country diva Alison Krauss, the pair have returned with “Raise the Roof.” Time has not diminished the magic. Once more, Plant alternates between a tense, gravelly croon and a manacled bluesy violence. Once more, Krauss is the perfect innocently-voiced foil or an ethereal ghost. And, significantly, T Bone Burnett has again assembled a crack ensemble and created a smooth yet robust sound. The dozen tracks, all unknown to me, range across American and British folk, country, and blues, and there is not a dud amongst them. My highlights include “Quattro (World Drifts In),” a Calexico folk-rock windswept song that kicks off with banjo and piano twinkling, then lurches into restrained passion; “Go Your Way,” which begins with Plant’s divine space-filling raspy whisper, over melodic guitar, then settles into an ear-worm farewell plea of release, like Led Zep hushed; and the busy, foot-stomping “Somebody Was Watching Over Me.”