Holy heck.

Thanks to Dangerous Minds, we recently came across one of the coolest -- and most bizarre -- pieces of rock history we’ve ever heard -- and it’s not even really rock and roll.

And maybe it’s not even music.

Reportedly, Nirvana’s Kurt Cobain assembled a mixtape of sorts called ‘Montage of Heck’ in the late ‘80s. He put it together using a four-track cassette recorder, and it highlights sounds (not full songs) from his collection, the radio, demos and more.

If you think you’re ready to hear it, give it a shot:

From Shocking Blue’s ‘Love Buzz’ (which would turn out to be Nirvana’s first song they ever released) to Metallica’s ‘Last Caress / Green Hell’ -- and some James Brown, Van Halen, Cher and Butthole Surfers thrown in for good measure -- ‘Montage of Heck’ showcases Cobain’s eclectic tastes and his knack for making memorable musical experiences, even in 1988.

More information than you could ever hope for can be found at LiveNirvana.com.

We're generally proud of our mixtapes, but we think 'Montage of Heck' puts us to shame. What do you think about Cobain's mixtape?

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