Sleazy and sexy’

When Nick Zinner met Karen O in a New York bar in 2000, musically speaking, they were polar opposites.

“She was doing very quiet and sorrowful singer-songwriter stuff,” remembers the guitarist for New York nuevo-garage-rock avatars the Yeah Yeah Yeahs. “And I had this experimental rock band that was a lot more sonically explorative, and a little hyper-analytical.”

The duo tried doing it O’s way in a project called Unitard, but found common ground over a drum machine, four-track recorder, and a mutual realization that they wanted to make “sleazy and sexy” music after the manner of the trashy rockabilly archetypes the Cramps.

Along with drummer Brian Chase, Zinner and O played their first gig later that year, opening for Sleater-Kinney and the White Stripes, and were soon labeled leaders of the downtown rock pack, along with the Strokes, Interpol and Liars. The hype built with two widely praised EPs, and was largely met with “Fever to Tell” (Interscope), the impressive 2003 full-length debut packed with primal riffage, courtesy of the charismatic O, high drama that’s both arty and anthemic.

Because the only instrument employed by over-the-top show woman O is her arresting voice, and the band has no bass player, Zinner, 28, is free to fill up the YYYs’ three-minute-and-less punk nuggets with crunching chords and buzzing effects.

“It makes you think outside of the box and try to come up with new solutions,” says the native Bostonian, talking on the phone from Omaha, Neb., the hometown of acclaimed songwriter Conor Oberst, a k a Bright Eyes, with whom he’s been collaborating. “I think it’s important to do as much work as you can with other artists, to stretch yourself.”

Zinner, who names Rowland Howard from the Birthday Party, Blixa Bargeld from Einsturzende Neubauten, and Neil Young as favorite guitarists, calls himself a “studio geek” who prefers recording to playing live. “I’d rather do without the traveling, the sound checks, and the getting sick,” he says, and claims to be “terrified” by the band’s forthcoming gig at the capacious Hammerstein Ballroom in New York, its biggest headlining show ever.

Anyone who has seen the YYYs perform, though, knows that even if Zinner would rather be home nursing a cold, the trio is a mighty live act. That’s in large part due to the fashionable O’s penchant for unfettered stage theatrics. “She frightens me sometimes,” says the guitarist, who says his Lyle Lovett-ish exploding do is the result of “how it looks when I wake up in the morning.”

“In Australia last month, we were really losing ourselves in what we were doing, and she was leaning up against a monitor and she fell off the stage.” Though no bones were broken, “she busted up her back and head pretty good,” Zinner says.

O, 24, and Zinner have been writing for “Fever’s” follow-up, which they plan to record in the latter half of this year. “We’ve got about six new songs that we’re doing in the set. They’re darker, more rhythmically oriented. Not so much party songs, which is good. All three of us are excited to be moving in a different direction.”