Has it really been 20 years? Soundgarden's 1994 classic 'Superunknown' has reached the two-decade mark and to celebrate, the band is releasing a variety of new 20th Anniversary edition sets on June 3. The band is teaming up with Loudwire, Ultimate Classic Rock and Diffuser.fm to give you a chance to win the 'Superunknown' Super Deluxe Edition box set as well as a 'Superunknown' vinyl set that's been signed by the members of Soundgarden themselves.

The 'Superunknown' Super Deluxe Edition Box is a five-disc package featuring the remastered album, additional demos, rehearsals and B-sides, while the fifth disc finds the album mixed in Blu-Ray Audio 5.1 Surround Sound. The collection also comes with a hardbound book with a lenticular cover, liner notes by David Fricke and newly imagined artwork designed by Josh Graham. It also features never-before-seen band photos shot by Kevin Westerberg.

As for the vinyl offering, the set is a 2-LP gatefold set with the remastered 'Superunknown' audio playing out on 200-gram vinyl. 'Superunknown' was responsible for giving fans such rock radio staples as 'Black Hole Sun,' 'Spoonman' and 'Fell on Black Days' among others. And yes, the vinyl set has been autographed by the band, making it that much more special.

So there you have it -- a pretty awesome Soundgarden package saluting one of their most highly regarded albums. How would you like to win the 'Superunknown' Super Deluxe Edition and Autographed Vinyl Set? All you have to do is enter your info using the form provided above and hope your name is chosen.

This contest will run through May 14. The official rules can be found here. To gain even more entries into the contest, tune in to hear 'Loudwire Nights With Full Metal Jackie,' airing weeknights on select stations across America on the air and online from 7PM to midnight. See the full station list here.

If you wish to pre-order your very own Soundgarden 20th Anniversary 'Superunknown' package, you can do so via the band's official store at this location.

Larger Images of the Soundgarden 'Superunknown' Super Deluxe CD and Vinyl Packages: