When Gregg Allman died at home in Savannah, Georgia on May 27 at age 69, we lost one of American music’s great voices, an artist who braided various strands of roots music into a thrilling new amalgam that ultimately had a massive reach. In the main, history tends to recognize the blisteringly soulful singer of The Allman Brothers Band as a founding father of Southern rock. But as the skilled keyboardist himself once lamented in regards to fussing over needless classifications, “Everybody has to have a name on music.” The group’s impact was broad. While the trajectories of Lynyrd Skynyrd, The Marshall Tucker Band, et al. would have been drastically different without the Allmans’ innovations, so would the ’90s jam-band scene, the alt-country/Americana movement, and strains of contemporary country. Chris Stapleton and Eric Church have both covered Allman Brothers songs.

Inspired by blues, soul, jazz, and rock ‘n’ roll, The Allman Brothers Band made a musical statement that was earthy, progressive, brainy and ballsy. And at the center of this perfect storm was Gregg – growling, moaning, and pleading the blues, and laying into his Hammond organ like some of mix of Jimmy Smith, Booker T. Jones, and Steve Winwood. Ballads were a particular forte. On tracks such as “Please Call Home” and “Melissa,” his voice did the heavy lifting, becoming the focal point of the performance by registering deep anguish and hushed delight, respectively. When the song fit him – as did “All My Friends,” from his 1973 solo disc, Laid Back – he could be devastating.

Gregg and his older brother Duane – whose brief life and career made him one of rock’s most enduring guitar heroes – played together in a long line of bands in the ’60s, but by the end of the decade, they partnered with whiz-kid guitarist Dickey Betts, bassist Berry Oakley, and drummers Butch Trucks and “Jaimoe” Johanson in Macon as The Allman Brothers Band.

Like their West Coast counterparts, The Grateful Dead, The Allmans found a way to reinvent American music for a new generation by marrying a deep knowledge of traditional forms with a seeker’s approach to composition and a virtuosic gift for group improvisation. On stage after stage, Duane and Dickey established an ongoing musical conversation informed by Chet Atkins, John Coltrane, B.B. King, and Ravi Shankar. And where most bands had a rhythm section, the Allmans had a polyrhythm section, a titanic trio that gave muscular-but-fluid bass lines room to dart around the two-man percussion squad’s loose-limbed grooves. The result was seductive and arresting, conjuring jazzy flair or ornery grit as the moment demanded. And significantly for that time – especially being from the South – they were one of the era’s few big racially-integrated rock bands.

It took a powerful frontman to plant a flag in the midst of all of that, and to inject a song’s lyric with true emotional impact. Whether the band was giving the blues a fresh coat of paint with dynamic reinventions of Blind Willie McTell’s “Statesboro Blues” and Sonny Boy Williamson’s “One Way Out” or creating their own musical instrumental language on tunes like the billowing “Dreams” and the churning “Whipping Post,” Allman’s voice coalesced the music’s character into something profoundly visceral. Never resorting to histrionics, Allman was the essence of cool. He seemed to have an endless reservoir of quiet intensity to dip into, and it made him the equal of the R&B singers he grew up admiring.

For all their studio prowess, The Allmans were always a primarily a live experience. The telepathic interplay and incendiary spark of 1971’s At Fillmore East not only helped the band break through to rock-star status, it is widely hailed as one of the best-ever live rock albums. Duane’s death in a motorcycle accident later that year changed the band’s sound forever, but they kept going until 1976, becoming rock ‘n’ roll royalty along the way.

Over the ensuing years, Allman struggled with substance abuse issues while maintaining a sporadic solo career and occasionally reuniting with his old bandmates. But when The Allman Brothers Band got back together to celebrate its 20th anniversary in 1989, it stuck. They rightly spent their final quarter-century reiterating a well-deserved rep as one of America’s greatest live bands, with their annual month-long Beacon Theater stints in New York becoming part of a legacy that transcended mere record-making.

Despite a 2007 hepatitis C diagnosis and a liver transplant in 2010, an ailing Allman released perhaps the best solo album of his career in 2011, the moody Low Country Blues, produced by T Bone Burnett. And he kept band moving forward. The Allman Brothers Band played its last show on October 28, 2014 at The Beacon. But Allman was working to the very end, finishing his upcoming solo album, Southern Blood.

Warren Haynes, who along with Derek Trucks made up the guitar section of the late incarnation of the Allmans, summarized the singer’s power in a farewell post on Facebook. “Every guitar player in every Southern town was listening to the Live at Fillmore East record and worshiping at the altar of Duane Allman and Dickey Betts. But the icing on the cake was always Gregg’s voice.”

Watch videos by The Allman Brothers Band on Vevo

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