While Soundgarden continue working on their first new album since 1996, the band will release a box set of their most popular albums next month.

Called 'Soundgarden: The Classic Album Selection,' the set features the original recordings of 1989's 'Louder Than Love,' 1991's 'Badmotorfinger,' 1994's Grammy-winning 'Superunknown,' and 1996's 'Down On The Upside.' Also included is 'Live on I-5,' a concert recording from 1996 that was first released last year.

That's pretty much every Soundgarden album, aside from their 1988 indie debut 'Ultramega OK.' 'Classic Album Selection' will be released on May 21, as reported by Loudwire. The box set also includes new artwork from Josh Graham, in the form of a set of mini-LPs in gatefold wallets with booklets.

Earlier this month, Soundgarden released their first new song in 15 years, 'Live to Rise,' which will appear on 'The Avengers' soundtrack. Their next studio album remains a work in progress, though Chris Cornell has said it won't sound like 'Live to Rise,' which he labels more "family-friendly" than the rest of the record. "Some of the songs on our new album are pretty far left of center, and sort of zero in on more of a hardcore Soundgarden fan and not necessarily a family that goes to see a film like that," he said.