Cannibal Ox with Keith Masters, Double A.B., Kenyattah Black, and I Realz. 9 p.m. Sunday, Jan. 13, at Brick and Mortar Music Hall. $15.
Underground hip-hop used to be a long swim upstream. It meant jostling from accusatory critics — how many times was the "granola" tag leveled at El-P or Aesop Rock? — and mystification from consumers. Cannibal Ox was the high priest of agit-rap in 2001, but the title afforded the duo few luxuries. It'd fare better now, with DIY hip-hop's approval rating at a record high — even bastard child El-P scores in the 80s on Metacritic. Cannibal Ox members Vast Aire and Vordul Mega aren't perfect; 2001's The Cold Vein's free rhymes could've benefited from some tightening. But this group's squirrelly, obsessive paranoia sounds timelier than ever in an America that spent 10 years color-coding terrorist threats.