What American is described as one of the most innovative and diverse rock musicians of his generation and released one of the earliest double albums in rock music?
Freak Out!:  Often cited as one of rock music's first concept albums, the album is a satirical expression of frontman Frank Zappa's perception of American pop culture. Frank Zappa: Frank Vincent Zappa (December 21, 1940 – December 4, 1993) was an American musician, composer, activist and filmmaker.
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