The title of this disc–which collects prison-related songs, from 1959 field recordings at Lousiana’s infamous Angola prison to Akon’s 2004 smash “Locked Up”–is pretty self-explanatory. What’s curious is that it comes from Germany, since it seeks to draw awareness to the alarming number of black prisoners in the U.S. Overall, In Prison provides an excellent cross-section of black prison music, from “Work Song,” Nina Simone’s tribute to chain gang blues, to “Living Proof” by Lifers Group, the assemblage of inmates at New Jersey’s Rahway Prison who were recruited to make a Scared Straight-like rap album for Hollywood BASIC in 1993. Ill musicology.