Yesterday (September 29) marked the 15-year anniversary of OutKast's Aquemini, the duo's seminal third album that solidified Big Boi and Andre 3000's status as hip-hop icons. It was future-funk and space-rap, bringing George Clinton down from the Mothership and Raekwon in from New York City, with Cee-Lo and Goodie Mob dropping by to lend a hand alongside Erykah Badu with Mr. DJ and Organized Noize providing a backbone. And it had classic tracks—"Rosa Parks," "Skew It On The Bar-B," "Mamacita," "Return Of The 'G,'" "Da Art Of Storytellin'"—almost every song was eminently quotable and had its own groove.

"Aquemini is the bridge between the pop brilliance of Stankonia and the Southern soul brilliance of ATLiens," says Killer Mike, who was around the group in Atlanta at the time through his friendship with Cee-Lo. "It's a beast within itself. For Southern music, period, it meant nothing was the same. Aquemini progressed our music 20 years."

The album marked a turning point for the two; Big had just had a second child, and Andre had begun experimenting with singing and Auto-Tune. Big was the resident hook-maker, and Dre was getting deeper into production. The album was also originally set to accompany a movie, with a script completed three months before the album's release and meetings scheduled regarding the project's casting. But the album was paramount. "We were side by side, camped out, sleeping in the studio for weeks at a time," says Big Boi. "Hip to hip. It usually takes us two to three years to make a record because we take our time; we ain't giving you that fast food, trying to meet a deadline. It ain't done until it's done sonically."

Sonically, it was unlike anything coming out of the South at the time and jolted the hip-hop community. "It was very experimental," Big Boi says. "That's when we really dove... We really started producing on the ATLiens album—me, Dre and Mr. DJ along with Organized Noize—so it was just a lot of time spent on the production on it." And lyrically the two stepped up, spinning tales about over-reliance on technology on one track while keeping their heads in the club on another.

"Whether it's Cee-Lo singing with Erykah all on one track with them or Big and Dre coming out from being wild and rambunctious teenage boys into grown men that were thinking about the world in a bigger way, everything about that record is perfect," says Killer Mike. "It makes me smile talking about it, and I can tell you're smiling. That's what you want a record to do; when you talk about it your elbow itches, your skin starts to twitch a little, because it feels good for your body to be re-awakened to the senses of what it felt like to listen to it for the first time. Aquemini is brilliant."

Fifteen years later, the album stands the test of time as one of the greatest pieces of work in hip-hop history. It may not have the sales of Speakerboxxx/The Love Below, the singles of Stankonia or the grittiness of Southernplayalisticadillacmuzik. But it remains an album that you can hold up as being an iconic piece of work in OutKast's career, maybe the iconic album of their reign—though you'd have to duke it out with those who believe ATLiens holds that distinction.

"It's classic—we make timeless classics, whether it's SouthernplayalisticadillacmuzikATLiensAqueminiStankonia or whatever it is," says Big. "We put it out, and that shit still stands the test of time. You can pop that shit in right now and still knock it. We take pride in doing that. There's no expiration date with our music." —Dan Rys (@danrys)

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