Sonic Sum is an American hip hop group from New York. It consists of Rob Sonic, Fred Ones, Eric M.O., and Preservation. The group was described by CMJ New Music Monthly as "hip-hop's Radiohead".In 1999, Sonic Sum released the first album, The Sanity Annex, on Ozone Music. It has received critical acclaim worldwide. XLR8R called it "one of the most criminally slept-on albums of the indie hip-hop boom". In 2004, the group released the second album, Films, exclusively in Japan. It was re-released on Definitive Jux in 2008.