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Bobby Womack, soul legend, session king and heavyweight collaborator, has died at the age of 70. The singer and R&B impresario had been diagnosed with Alzheimer's in 2013 and had battled colon cancer and diabetes prior to his passing.

Womack most recently delivered a critically lauded set at Bonnaroo. Before that, the Sam Cooke protege had been inducted into the Rock and Roll Hall of Fame in 2009, and 2012's The Bravest Man in the Universe was one of his proudest achievements of his career: "You know more at 65 than you did at 25. I understand the songs much better now ... It's not about 14 Rolls Royces and two Bentleys. Even if this album never sells a nickel, I know I put my best foot forward." Womack initially rose to fame with The Valentinos, and lent his guitar-picking prowess to integral tracks of both Cooke and Aretha Franklins discographies.

Friend and collaborator to many, Womack's partners in musical crime include Franklin, Janis Joplin, Sly and the Family Stone, Gorillaz and Damon Albarn. (Had Womack and Albarn not been playing at precisely the same time at Bonnaroo, we'd like to think the fields of Manchester would've been treated to an epic cameo on either stage.) Womack was about to include Stevie Wonder, Snoop Dogg, Rick Ross and Rod Stewart on that illustrious list, as he was hard at work on his next record with the aforementioned talents.