Courtesy of SHOWTIMEIf you just can’t wait until next month to catch the new Jimi Hendrix documentary Electric Church, you’re in luck. Rolling Stone is offering an exclusive preview of what’s in store.

The clip — which was filmed July 4, 1970 at the Atlanta Pop Festival — finds Hendrix, bassist Billy Cox and drummer Mitch Mitchell blazing through “Purple Haze.” The Atlanta Pop Festival performance wasn’t just another gig for Hendrix; it was the biggest U.S. show of his career, with an estimated attendance of 300 thousand people.

“Jimi was at the peak of his creative and commercial powers that summer,” says John McDermott, who directed the documentary. “There are so few examples of Jimi performing on film that this footage of him performing before the largest U.S. audience of his career is significant. Younger fans should take note that Jimi didn’t need set lists, dance steps, stage backdrops and lighting cues to connect with his audience.”

Jimi Hendrix: Electric Church will air September 4 at 9:00 p.m. ET on Showtime. The performance will also be released on CD as Freedom: Atlanta Pop Festival on August 28.

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