Nirvana's 'Nevermind' is arguably the most impactful rock album of the last 25 years. Its legend speaks for itself, selling over 30 million copies worldwide thanks to grunge masterpieces such as 'Smells Like Teen Spirit,' 'Come As You Are,' 'Drain You' and 'In Bloom.' You may think you've attained all the 'Nevermind' knowledge ever made public, but there are some new tidbits from producer Butch Vig and frontman Kurt Cobain that may deepen your understanding of the album.

In a new interview with Rolling Stone, Vig offers insight on the first time he heard the material which would later construct 'Nevermind.' "The week before I flew to L.A. [to produce 'Nevermind'], Kurt sent a cassette, which was done on a boombox," says Vig. "It was really terrible sounding. You could barely make out anything. But I could hear the start to 'Smells Like Teen Spirit,' and I knew it was amazing."

Referring to the 'Nevermind' recording timeline and sessions on the famous Sound City board, Vig paints an atmospheric disorder that arrived along with Nirvana. "They were living in this apartment complex, and it was chaos," Vig remembers. "There'd be graffiti on the walls, and the couches were upside down. They'd stay up every night and go down to Venice Beach until 6 in the morning. I'd go into the studio at noon and they'd wander in around 4."

Despite the insanity, the actual recording of the album went very smoothly, until Nirvana began to put the album's closing track, 'Something in the Way,' to tape. "No matter how subtly they'd try to play, it was too aggressive," recalls Vig. "Kurt walked into the control room and said it just had to sound like this – he was barely whispering, and playing the guitar so quietly you could barely hear it. It was mesmerizing. I pulled a couple of mikes in, and we built the whole song around it."

In the end, Cobain wasn't too happy with the album's production, with Vig insisting that the frontman's voice act as a dominant force within the record. Regarding 'Smells Like Teen Spirit,' Cobain would later reveal, "It's such a perfect mixture of cleanliness and nice, candy-ass production. . . It may be extreme to some people who aren't used to it, but I think it's kind of lame, myself."