In March, he canceled performances for the rest of 2017.
Born in Nashville, Tennessee, the rock star known for his long blond hair was raised in Florida by a single mother.
Allman's older brother Duane, a co-founder of the group and legendary guitar player, died in a motorcycle accident in 1971 at the age of 24, just as the band was enjoying its first big taste of success. Ironically, Allman lost to Tedeschi Trucks Band, the outfit that includes Derek Trucks, the longtime Allmans guitarist and nephew of original Allman Brothers Band drummer Butch Trucks.
Between 1975 and 1977, Greg Allman was briefly married to the actress and singer Cher.
His final album, recorded recently, was scheduled for release in September, Lehman added.
"In fact, I appreciate it all more and understand it much better", Allman told the Wall Street Journal in 2015. So they put out a live album, "At Fillmore East", recorded over two nights at a NY club. "He kept it very private because he wanted to continue to play music until he couldn't".More news: Steve Kerr's status for the NBA Finals remains unclear — Warriors GM
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With his band - The Allman Brothers Band - he is credited for creating one of the world's first southern rock acts, known for such tracks as Melissa, Ramblin' Man, Statesboro Blues, Midnight Rider and Whipping Post. "Listening to Allman Brothers "Live at Fillmore East", a record that never gets old".
No cause was given, but the statement said he had "struggled with many health issues over the past several years".
Allman's percussive Hammond B-3 organ playing helped anchor the Allman Brothers' rhythm section and provided a chuffing counterpoint to the often heated musical interplay between his brother and the band's other lead guitarist, Dickey Betts. Gregg was devastated, but he and the other band members agreed they should push on.
Gregg Allman's soulful vocals and Hammond organ were key ingredients in the group's sound, while he also wrote or co-wrote numerous band's enduring signature hits, including "Whipping Post", "Midnight Rider", "Melissa" and "Ain't Wastin' Time No More". Then 13 months after Duane's death, bassist Berry Oakley was killed in a similar motorcycle accident only a few blocks from where Duane had been killed.
"We used to write songs in a graveyard in Macon", Allman said. He is survived by his wife Shannon and his children, Devon, Elijah Blue, Delilah Island Kurtom, and Layla Brooklyn Allman as well as three grandchildren and a large extended family. I will never, ever take that for granted.
"He was more than just a producer for me, he was like a father figure nearly, " Allman said.
MARTIN: Thank you so much for telling us about this. I didn't believe it for a long time until somebody shoved it [Zappa's recording] right in front of my face and said here play it yourself.