The Twin Cities' underground hip-hop scene finally had its big day in the sun Sunday.

A who's-who of the local rap community turned out in the Metrodome parking lot for the first Soundset music festival, drawing around 12,000 fans, most under the age of 30.

It was by far the biggest crowd for a nearly all-local hip-hop concert and a clear indicator that Twin Cities hip-hop is no longer just an underground thing -- although not every performer appreciated being out in the daylight.

"I hate the sun," complained Anthony (Ant) Davis, the basement-loving producer/DJ in the Minneapolis hip-hop group Atmosphere, which headlined the 10-hour event.

Hanging out with Ant backstage, another of the fest's big hometown performers, albino rapper Brother Ali, shot back, "You think you got it tough."

Atmosphere and Brother Ali became nationally known thanks to their Minneapolis-based record company Rhymesayers Entertainment, the main instigators of Soundset.

After a decade-plus of hosting sold-out concerts at First Avenue nightclub -- and three weeks after landing its highest-charting album (Atmosphere's latest CD debuted at No. 5 in Billboard), Rhymesayers delivered on its most ambitious production to date.

A theory buster

Not only did Soundset trumpet Rhymesayers' popularity, it spoiled several popular theories: That lake-loving Minnesotans won't attend a big music fest on summer holiday weekends; that major-label recording artists, big corporate sponsors and corporate radio stations are all needed to put on a successful music fest, and that Minneapolis is not a hip-hop city.

"I think these are some of the best hip-hop acts in the country," said Walt Carlson, 22, who drove from Milwaukee.

With the music spread out over two stages and one tent, Soundset looked like a hip-hop version of the ever-popular Vans Warped Tour punk-rockathon -- also held outside the Dome in previous years. Soundset also included daredevil skateboarding exhibitions, a low-rider car show and booths featuring locally made hip-hop fashions.

Forest Lake High School students DJ Dexter, 16, and Fred Ogez, 17, have been fans of Rhymesayers acts for several years but had never been able to see any of them perform. "A lot of times the First Avenue shows are 18-plus, or it's hard for us to get there," said Ogez.

Dexter's first impression: "I think it's a really positive thing."

One more theory disproved: That a big hip-hop concert cannot be pulled off without violence and crime. Minneapolis police at the concert had no incidents to report after six hours.

Their own themes

All of the Soundset rappers eschewed mainstream hip-hop's stereotypical themes of bling-bling, guns and gang-banging. More than any other theme, Soundset's 30-odd sets of rappers stressed hip-hop's classic message to take pride in yourself and express your individuality.

Tattoo-covered, punk-rock-loving Minneapolis rapper P.O.S had a big chunk of the crowd singing along to his proud declaration, "No one will ever be like me."

Atmosphere rapper Slug (Sean Daley) -- the unequivocal star of Soundset and a co-founder of the Rhymesayers label -- seemed content to prove there are, in fact, a lot of young music fans out there like him. "A lot of these kids get put down for liking this music, or for being one of only 10 people in their high school who listen to us," he said before his fest-closing set. "I think this event is as much a validation for them as much as it is for us."

The fans seemed impressed. Rick Carey, 19, from St. Paul, said, "I'm not surprised so many people showed up, but I am sort of overwhelmed just by the enormity of the event."

Tim Smith, 23, of St. Louis Park, hopes the event will become an annual thing -- as do Rhymesayers and co-promoters Rose Presents. "I bet it just gets bigger and bigger if they do it every year," Smith said.

See Atmosphere's set list and fan comments at Chris Riemenschneider • 612-673-4658