PREVIEW Let's say you're a fan of dub — the remixed reggae subgenre pioneered by the studio experimentalism of King Tubby and Lee "Scratch" Perry — and I say to you, "Hey, come over. You have to hear this new dub CD I've got." Excited, but in a laid-back, dubby way, you roll a semistereotypical joint and skate down to my place on a longboard with big, soft wheels, smoking all the way. I throw on Another Sound Is Dying (Ipecac), the new Dub Trio CD. Immediately bombarded by crunchy guitar riffs and a distorted, growling bass line reminiscent of New York noise mavens Unsane, you become confused. Why the fuck is this metal record harshing my mellow?

Dub Trio — three spot-on musicians whose lists of recent session work reads like a who's who of putf8um hip-hop artists — eventually work island rhythms and delayed reggae riffing into the album, which may or may not bring your buzz back, Smokey. Yet the band is most true to the core idea of dub — the experimental manipulation of sound — in its willingness to destroy it, to go beyond the confines of traditionally dubable reggae material and say, "Fuck it, we can do a dub of this and that too." The trio's ambition, their sheer steeze to take the chains off the dub aesthetic, makes them fascinating, if not brilliant, and they go from nut-crunching sludge riffs to long, loping chill-outs without flinching. "What the guys in the beginning of dub were doing in the studio, we try to bring that element and re-create that concept live," drummer Joe Tomino said over the phone from New York City.

They stay true to the roots of dub in a wild new way: each band member controls effects for everyone else's instruments as well as their own. Which means Dub Trio's 12 Galaxies show will be a must-see: these guys can't just sleep through the same set every night. They've got to be on it, reacting to and changing the music as it's being made. "It's a constant way of thinking as one and listening to exactly what's happening onstage," Tomino said, "so you don't get in the way of the conversation or dialogue that's happening."

DUB TRIO With Foreign Island and Hour of Worship. Fri/15, 9 p.m., $12. 12 Galaxies, 2565 Mission, SF. (415) 970-9777, www.12galaxies.com