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Soundset 2011 is graduating from its underground roots with the announcement of surprise headlining performances from Big Boi and influential Native Tongues group De La Soul. Big Boi and De La will join usual-headliners Atmosphere and Brother Ali over Memorial Day weekend at the fourth installment of the Shakopee, Minn.-based festival.

While the Minnesota concert has already gained a solid reputation as a celebration of non-mainstream acts, this year's roster of talent ups the ante with the inclusion of some beloved out-of-town performers. In addition to Big Boi and De La Soul, the Eminem-cosigned supergroup Slaughterhouse, Curren$y and XXL's 2011 Freshman Class standout Mac Miller will also rock the crowd at the May 29 show.

This line-up also signifies the blurry boundary between underground and mainstream hip-hop in 2011. Once very separate entities with different artists and expectations, it seems that legacy underground artists, like Atmosphere, have widened their definition to include other D.I.Y. rappers with their own movements such as Curren$y, or even the ever-popular Big Boi.

All in all, there's something for nearly every hip-hop fan as the one-day festival covers three stages, while also including a breakdancing battle, MC battle, DJ tent, live painting exhibit, record fair, car show and a skateboarding contest. Tickets, which cost a reasonable $38, go on sale Friday, April 1, at 11AM through Ticketweb. Check out the full lineup here.