On their new Varcharz (Ipecac), German electronic duo mouse on mars shift gears once again. In sharp contrast to 2004’s Radical Connector, their most accessible, pop-oriented outing, the new disc is their most noisy and abrasive–though rubbery synth tones and propulsive, stuttering beats still anchor the tunes, the foregrounds are all unhinged, dissonant slashes and splatters. The roiling, heavily distorted electric bass on “Duul” seems to portend a typical hardcore punk spaz-out, but instead it becomes an in-the-red barrage of jumbled beats and biting electronics that bounces around like a fish out of water. No matter how aggressive things get, though, Mouse on Mars thankfully avoid the militaristic precision of Wax Trax-style industrial music; the tracks on Varcharz never settle into mechanical repetition, instead teetering perpetually on the verge of disintegration.

Mound Magnet (Thrill Jockey), the latest album by LITHOPS, aka Mouse on Mars member Jan St. Werner, doesn’t sound as extreme as Varcharz. But the general absence of fixed beats means it lacks a defining element of Mouse on Mars’s music; what’s left is amorphous, knotty, and jittery, packed with a restless parade of strange electronic sounds and textures.

Mouse on Mars headlines, Holy Fuck plays second, and Lithops opens. a 9:30 PM, Empty Bottle, 1035 N. Western, 773-276-3600 or 866-468-3401, $15. –Peter Margasak