Roots music of the kind that encompasses blues, folk and country is often perceived as still living in the past. Most artists choose to work within the boundaries of their chosen genre, maybe mixing in some soul, jazz or funk but still operating in a safe zone. When a musician decides to push at the edges and challenge the notion of what defines a genre – in this case the blues – the stage is set for some interesting music.

Gary Clark Jr. isn't new on the scene; he has been slinging his guitar for a few years now, but Blak And Blu feels like his true introduction and a step up from the success of the single Bright Lights. That song (and a couple of others) also appeared on his 2010 album, and it is his most accessible track with its blues, rock and indie (in a Black Keys sense) fusion. The good news is that there are other tracks as good as and often better than Bright Lights. Early on he unleashes his full searing, soloing arsenal on When My Train Pulls In, which tears and spirals out of the speakers for nearly eight minutes. Elsewhere he showcases his diversity with the rock'n'roll fun of Travis County, the disappointing hip hop Franti-isms of The Life, the Prince-like Please Come Home and the metallic lumber of Numb. Clark Jr. though sounds most at home when he is letting rip over psych-drenched blues rock and thumping out back-porch acoustic blues.

So yes, there is much to admire in his wide creative palette, but it feels like he has overplayed the diversity card when the real rewards come from the fresh air he breathes into the existing framework of the blues.