I’m wary of putting a Critic’s Choice button on anything I write about ORTHRELM, for fear that someone will take that recommendation to mean I’m recommending them for everybody. There’s no middle ground with these guys–in my experience anyone who isn’t fascinated by this stuff finds it completely unendurable. Mick Barr (of the equally alien duo Crom-Tech) and Josh Blair need nothing more than a guitar and a drum kit to distill everything that’s most exhilaratingly obnoxious about repetitive minimalism and arty, highly technical metal into a crisp, blindingly bright sheet of sound whose layers of detail shift and deepen as you listen, the way patterns come out in a TV screen filled with snow. Blair is the good cop, his drumming convincing you of the benefits of joining his tribe; guitarist Barr is responsible for the painful hazing. The intent behind their music seems to be abstract, but it occasionally sounds like ten years’ worth of bar-long transitions from prog-metal records all spliced together–that is, when it doesn’t sound like that electronic noise the baddies use to torture Chewbacca in The Empire Strikes Back. Orthrelm’s 2002 full-length debut, Asristir Veildroixe (Troubleman Unlimited), is 99 tracks in less than 13 minutes, which makes the record useful mostly for a cruel form of dog training. But last year’s OV (Ipecac) is one untitled 45-minute monster composed entirely of shifting rhythmic cells about a second long, and the shrill, needling guitar, frenetic drums, and numbing, obsessive, maniacal-bordering-on-sadistic repetition play your brain like a xylophone. It almost feels like a spoiler to say that it gave me vertigo when the music first broke open and shifted gears at about the 18-minute mark. –Monica Kendrick

The press release from local two-piece VOLTAGE says they’ll “have you shaking your ass while simultaneously asking yourself, ‘What is my ass?'” That’s a cruel promise to make if you can’t follow through, but on Building the Bass Castle Vol. 1 (Flameshovel) guitarist Todd Bailey and drummer Erik Schwartz, abetted by an assortment of scratch-built analog gizmos, got me fired up with the very first track. (There are no song titles, just a fucked-up-looking schematic and the formula V=IR–Ohm’s law, which I wouldn’t have had to look up if I were as mathletic as these guys.) The tune begins melodic and intricate, gets ferocious for a bit, and then calms down again, like Cul de Sac in a happy mood with about 30 seconds of panic sandwiched in the middle. Unfortunately the rest of the CD sounds like two record-convention vendors trying to drown each other out with Derek Bailey and Sammy Hagar LPs: it’s full of incomplete ideas, purposeful asymmetry, and implausible segues. –J. Niimi

Orthrelm headlines and Zombi plays third; Voltage and Big Nurse open. Fri 3/10, 8 PM, Beat Kitchen, 2100 W. Belmont, 773-281-4444, $8 in advance, $10 at the door, 18+.