Among postmillennial vocal-jazz developments, near the top of the list is Boz Scaggs’ reemergence as a richly gifted interpreter of standards. Now Scaggs takes a slight detour, physically and stylistically, landing at Memphis’ fabled Royal Studios for a stellar assortment of soul and country covers.

Though Scaggs is rapidly closing in on 70, his distinctive voice, with its trademark nasal twang, remains remarkably strong, showing little if any deterioration since the days of Silk Degrees and Down Two Then Left. The playlist draws almost exclusively from that same era.

Perhaps ghosts linger inside Royal Studios, because there is a powerful sense of Al Green, who recorded most of his most celebrated tracks there. Under the deft direction of producer Steve Jordan, who doubles as drummer-percussionist, Scaggs delivers a woebegone, weather-beaten “Rainy Night in Georgia” that easily rivals the desolation of Brook Benton’s, transforms the Moments’ “Love on a Two-Way Street” into a far bumpier ride toward heartbreak, and shapes a gorgeously slowed “Corrina, Corrina.” Mink DeVille’s “Mixed Up, Shook Up Girl” becomes a reggae-fueled tour de force, while Steely Dan’s “Pearl of the Quarter” benefits from added grit and gristle. And lest anyone forget that Scaggs is also an ace guitarist, he cooks up a blistering “Cadillac Walk” and a wailing “Dry Spell.”