Hard bop is a style of jazz that is an extension of bebop (or "bop") music. Hard bop incorporates influences from rhythm and blues, gospel music, and blues, especially in the saxophone and piano playing. Its bass playing is more varied than bop's, in part because of the prominence of such virtuosos as Charles Mingus and Ray Brown; it is in part intended to be more accessible to audiences unfamiliar with or not fond of bop. David H. Rosenthal also contends in his book Hard Bop that it is to a large degree the natural creation of a generation of black American musicians who grew up at a time when bop and rhythm and blues were the dominant forms of black American music and prominent jazz musicians like Tadd Dameron worked in both genres.
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