Big K.R.I.T. is my favorite rapper going right now, and I haven’t even heard his debut. I’ve been too busy bumping his mixtapes — he has dropped three in the last 15 months, and they’re all excellent, and free — to get around to actually buying his major-label studio album, Live From the Underground, out last month. K.R.I.T. is from Mississippi, and his version of hip-hop is steeped in the Southern rap tradition of guys like Pimp C, Chamillionaire, and T.I. He doesn’t seem content with revivalism, though. I don’t recall UGK ever rapping alongside any smooth jazz saxophones, as K.R.I.T. (who produces his own stuff) seems increasingly fond of doing. And few rappers from the A are as willing to hazard the kind of socially conscious sincerity that he lays down every fifth or sixth track. Still, he’s probably at his best when he keeps things breezy and street, as on “Rotation,” which goes I’m just rotating my tires, rotating my tires, rotating my tires, rotating my tires.