John O'Callaghan is an Irish Musician and DJ, mainly producing Trance music. He also produces music under the alias of Joint Operations Centre, Mannix and Stenna. He has also collaborated with fellow Discover artists such as Bryan Kearney, Neal Scarborough (as Inertia), Thomas Bronzwaer (as Lost World) and Greg Downey as well as more recently, trance hero Leon Bolier. His best ... Show More