By Eric Renner Brown
Updated August 03, 2015 at 08:54 PM EDT
Evening Standard/Getty Images

Next month marks the 45th anniversary of guitar legend Jimi Hendrix’s 1970 death. It also marks the arrival of more rarities from the Hendrix vault. Showtime will debut Jimi Hendrix: Electric Church, a documentary about Hendrix’s performance on Independence Day 1970 at the Second Atlanta International Pop Festival, on Sept. 4. A two-disc audio release of the show, named Freedom: Atlanta Pop Festival, comes out Aug. 28, and DVD and Blu-ray versions of the documentary, which include bonus footage not in the Showtime version, will hit shelves Oct. 30.

The recordings chronicle the festival some have referred to as the “Southern Woodstock,” which by some estimates drew 400,000 attendees to the Georgia town of Byron, according to a press release. The documentary includes interviews with Hendrix’s bandmates Billy Cox and Mitch Mitchell, along with Paul McCartney, Steve Winwood, Kirk Hammett, Derek Trucks, and Susan Tedeschi. Professionally shot footage of the festival went unused for decades when filmmakers couldn’t secure a deal to produce the documentary.

The most recent posthumous Hendrix live album was 2013’s Miami Pop Festival, which catalogued the star’s May 18, 1968 concert. The Hendrix estate also officially released his breakthrough 1967 Monterey Pop Festival concert—the one where all that famous guitar-burning imagery comes from—in 2007 and a box set of 1968 performances at San Francisco’s Winterland Arena in 2011. But Freedom is the first 1970 concert to be released since the early 2000s, when the guitar legend’s gigs at the Isle of Wight Festival and Berkeley Community Theater were released in 2002 and 2003, respectively.

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