WIKIPEDIA:

“ Mickey Hart (born Michael Steven Hartman; September 11, 1943) is an American percussionist and musicologist. He is best known as one of the two drummers of the rock band the Grateful Dead. He was a member of the Grateful Dead from September 1967 to February 1971, and from October 1974 to August 1995. He and fellow Dead drummer Bill Kreutzmann earned the nickname "the rhythm devils".

Career
Before joining the Grateful Dead, Hart and his father, Leonard Hart, a champion rudimental drummer, owned and operated Hart Music, selling drums and musical instruments in San Carlos, California.
Hart joined the Grateful Dead in September 1967, and left in February 1971 when he extricated himself from the band, due to conflict between band management and Mickey's father. During his sabbatical, in 1972, he recorded the album Rolling Thunder. He returned to the Dead in 1974, and remained with the group until their official dissolution in 1995. Collaboration with the remaining members of the Grateful Dead continues, under the band name The Dead.
Alongside his work with the Grateful Dead, Mickey Hart has flourished as a solo artist, percussionist, and the author of several books. In these endeavors he has pursued a lifelong interest in ethnomusicology [......] ”

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