Every budding guitar hero needs a live record to burnish the mystique, and Gary Clark Jr. delivers hard on this double-disc set. Live is as much a statement of his growing mastery as a singer and performer as it is a slippery addition to the “savior of the blues” hype that swirled around his 2012 debut Blak And Blu (hype that was well-deserved, it turns out). On trad numbers like “Catfish Blues” and Lowell Fulson’s “Three O’Clock Blues,” he reverently channels B.B. King, but with a soulful rocker’s feel that recalls a certain left-handed Seattle bluesman who redefined the genre. Clark opens “Numb,” the signature track from Blak And Blu, with a slide intro that morphs into a fuzz-distorted wave of sound—a slight return if ever there was one—while he pulls a fat Hendrixian tone from his Epiphone guitar on the solo for “Bright Lights.” So what’s next in the studio? The possibilities are tantalizing.