When Tom Petty passed away at age 66 in October 2017, millions felt the grief of his loss while experiencing gratitude for the many heartfelt rock songs Petty gave us over the decades. Now, new thanks can be directed to Petty for his carefully maintained musical vault of unreleased masters, and also to his family and collaborators for curating a selection for release. On Sept. 28, a four-CD boxed set titled An American Treasure will make these precious recordings available, and a first taste from 1982 has been already been unveiled, a previously unreleased song called "Keep A Little Soul."

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The collection was compiled by Petty's widow Dana, daughter Adria, Heartbreaker bandmates Mike Campbell and Benmont Tench, and engineer Ryan Ulyate. A two-CD version will also be released, but the 63-song tracklist for the fuller version — filled with alternate takes, unheard compositions and exceptional live performances — could start fans saving their pennies now for the more comprehensive offering.

In early 2017 Petty was named MusiCares Person Of The Year and musicians including the Foo Fighters and Norah Jones performed at his tribute ceremony. Jackson Brown commented that "all these songs are a part of me." The Lumineers praised Petty for his "universality," for writing songs that "feel eternal," and said they felt like they were "kindred spirits" with him. They singled out his B-sides as belonging on any other artist's greatest hits album. It's in that spirit that music lovers look forward to unreleased gems from his vault.

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The tracklist for An American Treasure contains live versions of classic titles such as "Breakdown," "I Won't Back Down" and "Into The Great Wide Open," in addition to the unearthed rarities. Songwriters, musicians, fans and new listeners alike are all bound to pore over his family's curated selection, a new legacy following the iconic body of work filled to the brim with Petty's against-the-odds rock spirit.

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