The new documentary Muscle Shoals recalls how interracial harmony in tumultuous times made possible a new kind of music. Leading African-American artists traveled to North Alabama — not exactly a place they thought they'd be welcome in the civil rights era — to jam with an all-white crew of session players. In little rooms near the wide Tennessee River, they perfected soul and anticipated Southern rock. (Muscle Shoals reveals how and invented that style, covering "Hey Jude.") The English rock eminence has long admired the Muscle Shoals, Ala., sound, the influence of which shows up in his more . But it took a Philly group shacking up in New York to help him work the Muscle Shoals magic .