Collections of Congolese rumba and soukous begin with an advantage—the music’s undulant undertone carries along so suavely that compiling it for flow is almost too easy. But does this double CD ever flow. Compiled by Gunter Gretz, Christian Scholze, and Jean Trouillet for the Frankfurt label Network, it offers an ideal combo of guns-ablaze forthrightness—Franco & Sam Mangwana’s “Cooperation” and Nyboma’s “Doublé-Doublé” is an ideal one-two—and historical survey; even the Cameroonian Manu Dibango gets a look-in.