Allman died young and until this year his recorded legacy had remained scattered; not repacked, unearthed and repeatedly rediscovered via reissues and compilations of nuggets panned from record label, studio and live recording vaults, like the still growing Jimi Hendrix catalog.

If not for his accidental death, Allman would have turned 67 on Wednesday, November 20. This year a superb memorial to Duane surfaced: a treasure trove of his studio recordings as well as very good examples of his playing with the Allman Brothers, Eric Clapton and others, packaged as the 129-track box Skydog: The Duane Allman Retrospective.

Combing through this definitive sonic study reveals much about his growth and development as a player as it lets listeners hear Allman's evolution from derivative teenage picker to capable sideman to musical visionary. It's remarkable how quickly he progressed. In 1965 Duane's initial recordings with the Escorts, the earliest band he shared with his brother Gregg, creak with rote R&B and surf licks. Two years later in their successive group the Hour Glass, he traces the same sonic terrain as fellow fuzztoned fretmen in era-bridled outfits like the Seeds and the Electric Prunes. But in mid-1968's Clarence Carter hit "The Road of Love" Duane's slide guitar debuts like a muscular thoroughbred in its first race, rippling with the same hyper-amplified grace as this set's performances of "One Way Out" and "You Don't Love Me" by the Allman Brothers at Fillmore East.

Let's take a look at tracks that most fans of Allman don't associate with his legendary canon: � "Twice A Man," Barry Goldberg Blues Band: This 1968 recording, cut mostly in Los Angles with Allman overdubbing his guitar in Muscle Shoals, didn't propel the Bay Area bluesman with a penchant for the genre's hard-core Chicago style into the same rarified air as Big Brother & the Holding Company, but it did give Allman a change to practice his slide chops. What's surprising is how thin and weak his tone was at this point, given the boldness of his soon-to-emerge signature voice on slide.