I don't belong here.

It's Friday night, and the sold-out Roseland Theater is crammed full of teenagers. Some of the girls are wearing little more than a bra and a tutu; most of the boys are shirtless. The headliner isn't even on yet and the air is already muggy. Around 11:20 pm, the lights dim. Five large, glowing letters descend from the ceiling: R-U-S-K-O. A scrawny dude sporting a floppy faux-hawk steps out on stage and perches himself behind a bank of DJ equipment. The opening guitar riff from Dire Straits' "Money for Nothing" blares from the speakers. And then it hits: wobbly, throbbing, equilibrium-rattling bass—bass so deep it's felt more than heard. The audience swells into a sea of waving hands and bouncing bodies. It doesn't stop for 90 minutes.

As I said, I don't belong here. And it's not just because I'm pushing 30. It's because I don't really know what the fuck I'm hearing. OK, I know it's dubstep, the predominant form of U.K.-based underground dance music of the late 2000s. That's about it, though. As a music fan—and especially as someone who writes about music—it's embarrassing to confess complete ignorance about a style that is steadily pushing its way into mainstream pop, thanks largely to this Rusko guy, a 26-year-old Brit who's worked with Rihanna, T.I. and Britney Spears. But electronic music in general has always seemed like an impenetrable culture, a kind of unnavigable forest of genres and sub-genres and sub-sub-genres. If you're going to try and wander in, you're sure to get lost, so best to stay away altogether. At least, that's been my thinking.

Even on its own, dubstep is a difficult style for an outsider to dive into, especially right now. Although it has galvanized American youth more than any other sound to come out of Europe this decade, it's a genre currently at war with itself. I first heard the term applied to the moody 2006 self-titled debut from enigmatic producer Burial, which All Music Guide calls "the first great dubstep album." But that record's haunting atmospherics are nowhere to be found in Rusko's candy-colored rave-ups, nor in the abrasive textures of L.A.'s Skrillex, another rising producer. All they have in common are tempos of 140 beats per minute and the use of overwhelmingly huge, bowel-displacing bass. Only a few years into its existence, dubstep is split along generational lines: the old-schoolers who prefer the subtle, dusky ambience it had originally, and the younger crowd who likes it loud, brash and, in the genre's parlance, "filthy."

Hoping to make some sense of this, I went to Jon "A.D." (who requested his real last name be withheld), 36-year-old owner of Anthem Records in Northwest Portland. Almost literally from behind the counter of this small, vinyl-stuffed storefront, A.D. operates Lo Dubs, a label specializing in dubstep and other bass-centric music.

"It's a dichotomy that happens with so many cultures. You always end up with a statement, and you end up declaring truths on both sides of that statement," A.D. tells me. "Yes, it's true that dubstep is bass music; yes, it's not true. Yes, it's true that dubstep is ridiculous and skronky and gets people waving their hands and doing stuff that looks like porn-movie moves, and yes, it's not true. Yes, it's true that a lot of people who are into it go to Burning Man; yes, it's not true. It carries on in that way, where you have to take it in both hands, and it's a matter of how deep you want to go in the conversation."

Truthfully, it's never been easy to pinpoint exactly what dubstep is, and that's crucial to its popularity. It's a genre built on a foundation of open interpretation. Initially, it spun off from garage—essentially the U.K.'s answer to Chicago house—via remixes that drew upon the eerie spatiality and fluid, melodic bass lines of Jamaican dub. Once it was given a name of its own, producers who'd become disenchanted with drum 'n' bass, grime and other, more limited styles, flocked to it, drawn in by the freedom of movement it presented. "It was liberating for people who made music," A.D. says. "You're working in a form of music that becomes very rigid in terms of its core principles, then all of a sudden you find out about this other structure that has so much space in it." It attracted listeners for much the same reason. Coloring in the crevices of the music with elements from a wide palette of influences—dashes of reggae, hip-hop, even punk and metal—dubstep reached people for whom dance music previously seemed foreign. 

"Before it got defined like this, it was really broadly approachable," says DJ Monkeytek, who along with A.D. co-founded Various, Portland's first monthly dubstep night, in 2006. And by "this," he means the "filthier" brand of dubstep, the more club-friendly form some have derisively labeled "bro-step." A.D. views the schism within the dubstep community with a sense of pragmatism. "You can look at it as a form of cultural gentrification, but you can't be that shitty about it, either," he says. "Anything that allows for there to be some light to be brought into somebody's life is a good thing."

Monkeytek (who also requested his real name be withheld), 40, is less charitable: "The people who are promoting that music are leaving behind cultural wreckage."

He doesn't mention it specifically, but he would almost certainly agree that See You Next Tuesday, the weekly dubstep night at the Crown Room, is an example of such wreckage. Every Tuesday, the beautiful people who usually prowl the clubs around Old Town on weekends come to hear what even DJ Kellan Cooper, who started the night with his friends Bobby Callman and Kenneth Avery two years ago, admits could be considered "bro-step." It's obviously an older crowd than that of Rusko, but the scene is much the same: a lot of ecstatic hand waving, not a lot of clothes. Cooper, with his gruff beard and a sense of style somewhere between skater and hip-hop head, appreciates both sides of the dubstep divide—this week, in fact, he's bringing in Ramadanman, a producer who even the purists feel is taking the genre in interesting directions—but he's unapologetic about wanting to create a party environment. "I like it," Cooper says. "I'm not going to lie."

For those with an attachment to the music's roots, See You Next Tuesday and Rusko represent the death of dubstep. Still, by the end of Rusko's Roseland set I'm beginning to realize why all these kids showed up. It's the same reason I went to punk shows in high school: For the sheer power of simply feeling something. And for better or worse, the bass that pummeled all of us for an hour and a half is something. Maybe I belong here after all.

SEE IT: Ramadanman plays Crown Room for See You Next Tuesday on Tuesday, April 26. See listings for more info. 9 pm. 21+.