Spank Rock appear to revel in contradictions. Rapper Naeem Juwan and production phenom XXXChange (Alex Epton) are an American group who record for the British flag-waving label Big Dada, they're the only underground rappers to talk about sex more often and more explicitly than Black Eyed Peas, and their tracks accept the limitations of old-school rap and bass music, but boast an agility that makes them sound positively post-millennial. Sex is all over this record, appearing on nearly every track, from the "ass-shaking competition champ" in "Back Yard Betty" to the 50 Cent-style partying going on during "Coke & Wet." Virtually every track -- notable exception: "Rick Rubin" -- either references or focuses in on what you learn in anatomy and apply in life. Juwan may sound like a juvenile Q-Tip (minus the abstract rapping), but he's one of the brightest young American talents of the mid-2000s, using his voice in delightful ways (some helped along by post-production). Meanwhile, on the production end, XXXChange concocts a series of deep bass hits, digital claps, and the occasional cougar scream to recall the type of stark, echoing productions and drum programming rarely heard since the mid-'80s. It's all performed so perfectly, and informed so well by Juwan's lyrical finesse, that the vintage feel never seems like a crutch. Best of all is "Bump," where first Juwan takes a few minutes for a speed rap, then guest Amanda Blank enters halfway through, initially giving one of her stiffest Roxanne Shanté impressions but, in a heartbeat, shifting into a higher gear like a sports car blowing away the competition.