TERA MELOS, POSTMADONNA, HEAVY PETTING

If the word "math" triggers fear and alienation, don't fret. Sacramento's Tera Melos are one of the best "math rock" bands active right now, and you won't need a calculator to follow their muscular, reactive guitar work. In their wildly erratic yet seamless instrumental weaving, time signatures shift more rapidly than 21st-century wildfires and lightning-paced riffs diffuse into something else entirely within seconds. With last year's X'ed Out, the trio's melodic progressive punk provides a soundtrack for those who prefer music conducive to thinking or feeling rather than the absentminded neon grind. Tonight's bill is also boosted by two of Seattle's finest exports into the math- and instrumental-rock canon: Postmadonna's post-caffeinated, hyperspasmodic math rock has earned praise on these pages before. Their supercharged mad-scientist energy is currently unparalleled in Seattle for its catchy weirdness and sing-along-ability. With the young Eastside four-piece now signed to Tetra Records, parallel universe domination seems inescapable. Up-and-coming trio Heavy Petting should also impress those seeking smart instrumental rock. Their expansive and powerful style flirts with lush and looming post-metal atmospheres. Crocodile, 8 pm, $10 adv.

PROTOMARTYR, GRAVE BABIES, UNNATURAL HELPERS

There is something decidedly "vintage"-sounding about Detroit-based punk act Protomartyr, and I'm not saying that in an American Apparel Does Grunge sort of way. These wiry post-punk sounds seem directly misplaced in time on their sophomore full-length, Under Color of Official Right. They look back to bands with a dirty, minimalist style like the Fall or proto-punks Crime for direction rather than lackluster spin-off contemporaries. A very natural addition to the current Hardly Art roster, Protomartyr's proto/post/post-post-punk lands in the modern cred-worthy realm of METZ and the Men. I enjoyed this a lot more than I was expecting, and I am looking forward to seeing how they can expand on these pop-hook-infused, Mark E. Smith–indebted, ill-mannered punk lovefests. Garage-punk standbys Unnatural Helpers and cool ghouls Grave Babies also provide fitting local support for the night. Black Lodge, 9 pm.