a&eletters@sfbg.com

TREATISE If, 20 years from now, recumbent in your easy chair with your slippers and favorite bong, some snot-nosed younger sibling should ask you about the zeitgeist of late '00s underground metal (apparently the kid took an art history class), you might consider introducing the shaver to San Francisco's Black Cobra, a two-piece that almost certainly could not exist at any other point in time.

From the tarry primordial soup of Cobra's cavernous low-end emerge the various slimy, naked hallmarks of an increasingly protean metal scene — unapologetic Sleep worship, reverent nods to punk and hardcore cross-pollination, and a healthy dash of retro-metal swagger inform the band's gargantuan riffs. Nothing about this approach feels like it's been calculated for maximum relevance; instead, Black Cobra's molasses-thick sound comes off as the happy end result of two longtime fans who came to the conclusion that they could, and should, create the music they wanted to hear. And while the band — Jason Landrian on guitar/vox, and Rafael Martinez on drums — has become more professional-sounding over the course of three full-length releases, the same caustic resin hit of recklessness permeates their newer material.

Black Cobra may not be High on Fire-monumental, or as thought provoking as Stephen O'Malley's latest art-drone opus. But if nothing else, Landrian and Martinez are doing their part to wrestle metal from the clutches of lifeless robo-shredders, and making some damn heavy music in the process.

BLACK COBRA

With 16, Serpent Crown, dj Rob Metal.

Tues/8, 10 p.m. (doors 9 p.m.), free, 21 and over

The Knockout

3223 Mission

(415) 550-6994

www.theknockoutsf.com