To Kassa Overall, Detroit is a city that represents both source and absence. Overall’s father, Charles, moved away from Ecorse, a steel town just south of Detroit, in his twenties, and never returned, cutting ties with family and traversing the country, eventually settling in Seattle. Much has been made about the Great Migration of African Americans who turned away from the South toward higher-paying jobs in more tolerant northern cities. But there were other, smaller migratory waves of people who decided to leave northern cities such as Detroit, disillusioned by racism and the consequences of white flight and subsequent economic collapse, in search of a better life elsewhere. Overall has spent little time in Detroit and has little contact with his family members in the region. Yet he has always wanted to connect with his people. In a way, he has. It is significant that several of his greatest musical influences have hailed from the Detroit metro area, including the pianist Geri Allen, with whom Overall played for six years, and the drummer Elvin Jones, who became one of Overall’s earliest mentors. Detroit is also the home of Karriem Riggins, the drummer-producer who was one of the early innovators of the intersection of jazz and hip hop, as well as J Dilla, the hip-hop producer who, as Dan Charnas’s recent biography illustrates, reinvented rhythm with non-quantized electronic drum patterns.