Like so many artists who don't rest on convention, Marnie Stern is an acquired taste. Though her sometimes screechy voice and caffeinated, angular songs aren't often love-at-first-listen, she's well worth some attention. Stern pulverizes the guitar-hero archetype that has been set in cultural stone by Nigel Tufnel, lead guitarist for fictional heavy metal group Spinal Tap. Tufnel so closely resembles real-life guitar royalty--with his masterbatory solos, hollow intellect, and inflated ego/pelvis--that he makes it difficult to take the real thing seriously. Stern is analogous to Tufnel in a couple of ways. Her playing is impressively savage, creative, and cathartic, and she adopts Tufnel's tools, using them progressively elsewhere. For texture, she employs the hammer-on technique (think of the guitar line that runs through AC/DC's "Thunderstruck"), which is difficult to use excessively without implications of cheesy gimmickry, but she pulls it off. In Stern's hands, it's percussive, weaving head-spinning rhythmic threads with the equaled talents of a technically accomplished and eccentric drummer (Hella's Zach Hill). Stern's lyrics, however, easily transcend the guitar-hero mold. A quick subject matter sampling of stereotypical metal music includes sex, drugs, and rock and roll cliché, or teenager-inspiring taboos, like hell and nihilism. But Stern's songs are endearingly philosophical--like pep talks for people who think too much, pushing for optimism and against lethargy. This line from "Steely" is a good example of her positive thinking via abstract existentialism: "I'm like a raging animation/ I'm wondering what it's like to be one/ I'm hoping it's true / I'm hoping for you!" Also on the bill tonight is Gang Gang Dance, a Brooklyn-based group pushing on the expectation of electronic indie rock and world music, and achieving inspiring results. 8 p.m. Larimer Lounge, 2721 Larimer St., $10, 303-291-1007