It's a sign of Joe Bonamassa's increasing profile that he got blues legend B.B. King to guest on his eighth album Black Rock -- and if what you're doing is good enough to rope B.B. in, there's not much reason to change, so Bonamassa doesn't tinker with his formula here, retaining a little of the folky undertow of The Ballad of John Henry, but with its remaining roots in a thick, heavy blues-rock more redolent of '60s London than the '50s Delta. Of course, Bonamassa has never shied away from his love of Brit-blues, even underscoring it with a good streamlined cover of Jeff Beck's "Spanish Boots," but he retains a healthy respect for all manners of classic blues, kicking out a Chicago groove on a cover of Otis Rush's "Three Times a Fool," reaching back to Blind Boy Fuller for "Baby You Gotta Change Your Mind" and ably replicating B.B.'s latter-day soul groove on a horn-smacked cover of Willie Nelson's "Night Life." Bonamassa has an ear for non-blues writers too, cherrypicking Leonard Cohen's "Bird on a Wire" and John Hiatt's "I Know a Place," tying it all together with beefy lead lines, but the provocative moments on Black Rock are all self-penned, whether it's the clattering stomp "When the Fire Hits the Sea," the British folk lilt of "Quarryman's Lament" and "Athens to Athens," or the droning dramatic epic "Blue and Evil." These are easily the most intriguing songs here, suggesting Bonamassa realizes that the familiar covers allow him to stretch out elsewhere, and while it might be interesting hearing him follow this path for a full album, what's here on Black Rock is both satisfying and admirably, if reservedly, ambitious.