After throwing fans of his campfire serenades off guard with the jam-heavy live album Try!, Continuum confirms John Mayer’s transformation into a 21st-century soul man with serious blues-rock chops. And for Mayer, that shift means more than just casting his songs in a gospel glow, but also speaking to political unrest atop the laidback shuffle of “Waiting on the World to Change.” Ultimately, the growth Mayer exhibits here can be gauged not just by his shred-tastic cover of Hendrix’s “Bold as Love,” but by the fact he answers it with “Dreaming with a Broken Heart,” a lighter-waving anthem to call his own.