Jim Morrison Fanclub
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Jim Morrison always had a certain cadence to his singing that seems to be strongly influenced by tribal chant. He gets down to the very roots of blues singing in that respect- the blues grew out of the folk music of African tribes- Morrison's interpretation of the blues seems much closer to this than most others in his time period. The "tribal" feel, I think, also comes from Native American influences as well- melding together into something unique.