It's hard to believe two decades have gone by since the initial release of Nirvana's groundbreaking album, Nevermind. Released on September 24, 1991, Nevermind was single-handedly responsible for the rise of alternative rock in the 90's. With the deluxe edition set to be unleashed next month, bassist Kris Novoselic and producer Butch Vig shared stories about what went on in the studio during the making of Nevermind.

Speaking to Rolling Stone, Vig remembers the trio of kids who came to his Smart Studios in Madison, WS in April of 1990. Kurt Cobain, Novoselic and then drummer Chad Channing drove 1,900 miles nonstop from Seattle.

"They rolled up in a van and they probably hadn't taken a bath or shower in three or four days," said Vig.

The band ran out of money for studio time in five days but they made the most of what they could.

"We had this motel room, and we would go to Smart Studios and work every day," Novoselic said. However, the recording sessions weren't exactly smooth sailing according to Vig.

"Kurt was charming and witty, but he would go through these mood swings," Vig revealed. "He would be totally engaged, then all of a sudden a light switch would go off and he'd go sit in the corner and completely disappear into himself. I didn't really know how to deal with that."

Eight demos from that week's session are included in the 20th anniversary edition of Nevermind, which will be available September 27 on various formats and packages. Offerings range from a single CD to a 5-disc box set. Goodies include a remastered edition of the album, b-sides and rarities and a live Halloween show from 1991. The reissue was carefully crafted by Novoselic, Dave Grohl, Vig, Nirvana's management and representatives from the Cobain estate.

As for the mixing of the album, Vig would once again have to deal with Cobain's quirks.

"I'd be balancing the drums and the guitars," says Vig, "and Kurt would come and say, 'Turn all the treble off. I want it to sound more like Black Sabbath.' It was kind of a pain in the ass."

Are you excited about the 20th anniversary edition of Nevermind? Does it contain enough extra content to make it worth buying? Tell us below.

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