Group Theory: Black Music is a stunning new statement from South African drummer and composer Tumi Mogorosi. Standing in the lineage of South African greats such as Louis Moholo-Moholo, Makaya Ntshoko and Ayanda Sikade, Mogorosi is one of the foremost drummers working anywhere in the world, with a flexible, powerful style that brings a distinctive South African inflection to the polyrhythmic tradition of Elvin Jones, Max Roach and Art Blakey. Since his international debut on Jazzman Records in 2…