Courtesy Soundgarden via Instagram

As previously reported, Soundgarden will commemorate the 20th anniversary of the release of Superunknown with two deluxe editions of the album, and also a vinyl version. The deluxe editions will include previously-unreleased rehearsal recordings, demos and b-sides. They are set to be released on June 3.

To hold fans over until then, the band has released a demo version of "Black Hole Sun," one of the two Grammy-winning tracks from Superunknown. It's streaming on the band's SoundCloud page now, and sounds pretty much like a rougher version of the original -- rawer somehow, but still very recognizable.

Superunknown debuted at number one the week it was released in March 1994 and remains Soundgarden's best-selling album.

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