When Das Racist debuted with 2008’s “Combination Pizza Hut and Taco Bell,” it was difficult to tell if the Brooklyn duo were just outsider scoundrels poking fun at hip-hop. Sit Down, Man clears things up: Victor Vazquez and Himanshu Suri are rap nerds who uncoil verses crammed with obscure, wide-ranging references and cutting social observation. It’s Rawkus Records-era indie weirdness without the purist rigidity. Snagging twitchy beats from El-P, Diplo, Dame Grease, and others, they express adoration for hip-hop’s wonderfully sprawling meta-ness. And on the satirical fiasco “Fashion Party,” abetted by Chairlift’s glossy synths, they murmur their punch lines with effete élan: “Wafers and crackers, famous actors / Duck confit, pinot grigio / Hummus with miso.”