Transmission Festival is a large indoor trance music event originally based in Prague, Czech Republic at the O2 Arena. In March 2014, the festival was held for the first time in Bratislava, Slovakia.

John O'Callaghan, is an Irish musician and DJ, who mainly produces trance music. He also produces music under the aliases of Joint Operations Centre, Mannix, Henrik Zuberstein, and Stenna. He has coll