At some shows, the opening act perfectly complements the headliners; at others, they're a puzzling contrast. Tonight, Seattle's sweetly psychedelic, shoegazing pop rocker (and producer du jour) Erik Blood opens for a pair of smirking, sample-happy, copyright-flouting electronic pranksters, and the through-line is anyone's guess. The Bran Flakes make bouncy, brassy, bite-size party music out of kiddie cartoon themes, authoritarian voice-overs, and whatever music is at hand; the Evolution Control Committee prefer higher-profile sample sources—Public Enemy mashed into Herb Alpert, Dan Rather into AC/DC—put to more overtly political/satirical ends. It should all be a weird, good time. (Chop Suey, 1325 E Madison St, 324-8005. 9 pm, $10 adv/$12 DOS, 21+.)