Throughout the initial two decades of their career, Aerosmith were doing all they could to keep it together personally and musically. By the advent of the '90s, however, they were riding a career high in both respects.

Sober and having dominated the rock charts with the 1987 comeback album Permanent Vacation and its follow-up two years later, Pump, the band - and former label Columbia – decided to empty out the vaults from their first 10 years of existence on Pandora’s Box, released Nov. 19, 1991.

Spread out across three discs, the collection delivered something for everyone: There were hits for the casual fans, deeper cuts for those looking to go beyond “Dream On” and “Walk This Way,” and a bunch of studio jams, instrumentals and unreleased versions of songs for the hardcore Aerosmith followers. It had a special appeal to the early listeners who weren’t a fan of the growing number of ballads the group was doing in the latter part of the 80s – those who preferred the raw, harder rocking, rooted in blues and '60s English rock style of the Boston act.

The real meat was in those never-before-heard songs and the jams that would turn into fully realized tracks. Highlights include the almost Black Sabbath-esque “Soul Saver” – which morphed into Aerosmith’s heaviest track, “Nobody’s Fault” – and the bluesy slither “Let It Slide,” a rough form of “Cheesecake.”

Listen to Aerosmith's Previously Unreleased Song 'Soul Saver'

It isn’t all Aerosmith based either: “S--- House Shuffle,” the brief instrumental by Joe Perry, came from his final session during the disastrous Night in the Ruts recording cycle after which he’d exit the group for a five-year period. That small bit provided the foundation for “South Station Blues” from the guitarist’s second solo album, I've Got the Rock 'n' Rolls Again, and also appears on Pandora’s Box.

Perry wasn’t the only Aerosmith guitarist who left the band, and Brad Whitford’s foray into Whitford/St. Holmes is represented by the song “Sharpshooter.” Not one to be left out, singer Steven Tyler’s pre-Aerosmith outfit Chain Reaction opens up Pandora’s Box with the Yardbirds-inspired “When I Needed You.”

Covering the artists who influenced them always appealed to the members of Aerosmith, and there’s a handful of interesting ones on Pandora’s Box, most notably their third released (thought first recorded) take on a Beatles song, this time “Helter Skelter” from the Toys in the Attic sessions. Elsewhere is the Otis Rush blues jam “All Your Love,” and a loose try at the Lovin’ Spoonful’s “On the Road Again.”

That said, Pandora’s Box could’ve been a more streamlined package. At the time of its release, Aerosmith had already put out two collections – Greatest Hits (1980) and Gems (1988) – and this set features 21 of those 22 tracks in one arrangement or another. (Often, it’s a live version or a remix of the original.) Nevertheless, Pandora’s Box remains a valuable snapshot of the lean, formative years of Aerosmith.

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