To his credit, Clapton has continued to dance with the genre what brung him. This album is a dream for purists, meaning the “Mr. Johnson” in question is not Keyshawn, Randy or Magic. He is Robert Johnson, the 1930s blues pioneer from Mississippi. Featuring 14 tunes written and previously recorded by Johnson, this album is full of the sweetly urgent ache of the blues. Clapton uncannily captures the appropriate sound; his voice is weathered and true, his guitar playing vibrant and inventive. And he and coproducer Simon Climie chose wisely in picking his sidemen. Notable players include keyboardist Billy Preston, whose vigorous backing on the exhilarating jump blues “They’re Red Hot” evokes pianists in the great stride and boogie-woogie traditions. Jerry Portnoy adds his plaintive harmonica, Nathan East his sturdy bass, and everything rides on the reliable engine of Steve Gadd’s drumming. Clapton has explicitly alluded to his blues inspirations before, of course, and has even recorded Johnson songs in the past, But this tribute is not only an honorable gesture. What might have been merely dutiful is profoundly musical, soulful and thoroughly enjoyable.