Born 1963, Rick Rubin is one of the most infamous producers of modern music and has been responsible for the birth of 2 labels: Def Jam, with Russell Simmons in 1984 and Def American Recordings, Inc. in 1988 (later changed to American Recordings). He has produced some of the "heaviest" tunes if not sonically (Slayer, Public Enemy) then emotionally (Johnny Cash, Mars Volta).