Rick Diamond/GABB14/Getty Images for Blackbird ProductionsJackson Browne‘s friendship with the late Gregg Allman dates back to the late 1960s, before Gregg and his brother Duane formed the Allman Brothers Band. Now, the famed singer/songwriter has penned a heartfelt tribute to the Southern rock pioneer, who died Saturday of complications from liver cancer.

“Allman was one of the most gifted singers of the last fifty years,” Browne writes on his Facebook page. “He was a blues singer first, and he was so natural, and so soulful, that when he sang songs that were written in a major scale, he found all the most soulful and expressive passages through those changes.”

Jackson notes that an example of this was Gregg’s cover of his tune “These Days,” which appeared on Allman’s first solo album, 1973’s Laid Back.” “He slowed it down, and felt it deeply, and he made that song twice as good as it was before he sang it,” Browne maintains.

Browne also reveals that he spoke with Allman during the week before his death, and “got to tell him how much his music and his friendship has meant to me.”

Jackson also shares some details about the duet version of his early song “Song for Adam” that he and Gregg recorded for Allman’s forthcoming album, Southern Blood.

“He and [producer] Don Was sent it to me to sing on, and I did,” writes Browne. “That song, the way he sang it and where he sang it from — at the end of his life — well, he completed that song, and gave it a resonance and a gravity that could only have been put there by him.”

Jackson closes by saying, “I will miss him. I send my deepest condolences to his family, his bands and crews, and all those who knew him and loved him.”

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