Conflicting impulses shape the agenda on Dilated Peoples’ bracing fourth album. In the wake of the chart success of Kanye West and the tiresome Black Eyed Peas, the Los Angeles hip-hop trio has surely felt the pull of the mainstream: 20/20 boasts a couple of catchy, R&B-flavored tracks designed to pass for pop entertainment. Their hearts aren’t in it, fortunately. Beyond token sweetening, MCs Evidence and Rakaa show little interest in playing nice, whether performing silly skits about getting high, calling the commander in chief “Lucifer,” or considering the use of armed self-defense to battle racism (a recurring Peoples theme). Reinforcing the conversational raps and fat, emphatic beats, nimble DJ Babu threatens to steal the show with delightfully furious scratching that confirms a stubbornly old-fashioned outlook. As “Another Sound Mission” observes, “Can’t beat ’em, join ’em?/That’s for submission.”