They were ugly, beautiful, and then ugly all over again. They were obscure, influential, and then once again obscure. They were the Pixies and — thanks to a new documentary premiering this week at the South by Southwest Film Festival —  they're being immortalized as one of the great contradictions in modern music.

"The film is called 'loudQUIETloud,' and that's kind of what it was," director Steven Cantor recently said. "The Pixies had a reunion tour in 2004, and we followed them around the whole tour, and they are four very remarkable people. Very different people from each other, in wildly different phases of their lives. Onstage there was this incredible camaraderie and chemistry, and they sounded fantastic.

"And offstage," he added, grinning, "they don't really talk to each other that much."

If you're unfamiliar with the names Charles Thompson, Kim Deal, Joey Santiago and David Lovering ... well ... you're probably in the majority. The Pixies hardly broke any sales records during their original 1986-1993 run, their music videos were rarely seen by anyone but insomniacs, and you'd be hard-pressed to find "Monkey Gone to Heaven" available at your next karaoke party. Reminiscent of other ahead-of-their-time acts like the Velvet Underground or Big Star, however, the people who did buy their albums went out and started up their own bands, and proceeded to rip them off with the greatest of reverence.

"I'm a huge Pixies fan," Cantor insisted, listing himself among a group of creatively minded admirers ranging from Modest Mouse to Queens of the Stone Age. "I heard they were getting back together, and my [co-director Matthew Galkin] and I were on the phone trying to get tickets. We were on the phone and were like, 'Wait, we gotta make this movie.'

"We called their manager and he was like, 'Yeah, there were 17 other people who sent in their proposals,' " the director sighed.

If you remember a band named Nirvana who built upon the "loud chorus/quiet verse/loud chorus" aesthetic with minor hits like "Smells Like Teen Spirit," then you know the Pixies. If you remember the key moment at the end of "Fight Club" when Edward Norton says, "You've met me at a very strange time in my life" while watching all of society collapsing around him, then you know the Pixies and their song "Where Is My Mind?" Indeed, if you've ever a heard a soft intro give way to a thunderous chorus in the last two decades, you've been touched by that band you've never heard of.

"I don't think documentaries should necessarily have a visual style that you impose on a subject," Cantor said of the simple stare of his camera's lens. "You just think about what the subject is going to be, and then come up with a style and look that will suit that topic."

For this particular project, that subject was the bandmembers' none-too-subtle disdain for each other, manifesting itself in a collection of love/hate moments that bring a double-meaning to the film's title. After their differences tore them apart in the early '90s, their solo projects were constantly met with questions about whether they'd ever reunite. When they finally did, Cantor and Galkin were there to capture the ugliness, the beauty and the noise that made them as contradictory as ever.

"Onstage, there was like this electric chemistry and fans going crazy and telling them 'Kim Deal is God' and 'Charles, I wanna have your babies,' " he said, referring to some of the footage that fuels the film. "They're just these rock gods. And offstage, and behind the scenes, they're very regular people just living their lives, each with their own struggles."

"There was pretty crazy tension," he continued. "Kim was trying to stay sober through the whole tour; she had insisted that it be a dry tour. Dave the drummer's father died, and that kind of made him go off the rocks and start drinking ... so that created some tension."

"Charles, Frank Black, the lead singer, he was kinda into his girlfriend, soon-to-be wife, who's pregnant now with their second baby, and Joey was doing a documentary," Cantor shook his head. "Not really in sync offstage, but amazing together."

Some things never change, and other things — like the Pixies' music — are better off that way. "There's no new stuff," Cantor said of classics like "Here Comes Your Man" and "Gouge Away" performed in the film. "It's all old stuff. They don't have a new album or anything."

After South by Southwest in Austin, the film is aiming for a major release that might help polish up the legacy of a band that history has largely forgotten. The music in "loudQUIETloud: A Film About the Pixies" is anything but steady; the love of their loyal fans, however, remains loud-loud-loud.

— Larry Carroll