Mitchell died at Methodist University Hospital in Memphis at 7:25 a.m., more than two weeks after he suffered cardiac arrest Dec. 19, said his son, Lawrence Mitchell.
In the 1970s, Mitchell also owned Hi Records of Memphis, the label that produced some of Green's biggest hits. Green, also from Memphis, was flying to Australia and unavailable for comment Tuesday.
At Hi, Mitchell was responsible for several instrumental hits of the 1960s and helped the careers of Green and singer Ann Peebles in the 1970s. Even in later years, Mitchell stayed busy at his studio, working with then-emerging talents like Mayer and Anthony Hamilton.
Most recently, he wrote string and horn arrangements for Rod Stewart's new album of R&B covers, and produced a still-unreleased album from soul kingpin Solomon Burke.
He received a Trustees Award from the Grammy Foundation in 2008.
A trumpeter, Mitchell and his band provided the musical entertainment at several New Year's Eve parties for Elvis Presley at Presley's Graceland home. A Memphis boulevard was named in his honor in 2004.
Mitchell was born and raised in Ashland, Miss.
Family members said funeral arrangements have not been made, but there will likely be private services and a public memorial.
Other survivors include two daughters.
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