John O'Callaghan is an Irish trance DJ and producer from Navan, Ireland, born in 1982. He works mainly in electronic music and is associated with trance, progressive trance, uplifting trance, vocal trance and melodic trance. His output also extends across dance, deep house, disco, dubstep, electronica and future bass.

Aliases and projects

He releases music under several aliases, including Joint Operations Centre, Mannix and Stenna. Stenna is also listed among his member names, alongside Inertia, Cartel and Key4050.

Collaborations

O'Callaghan collaborates with other Discover artists including Bryan Kearney, Neal Scarborough under the name Inertia, Thomas Bronzwaer as Lost World, and Greg Downey. One of his best-known tracks is Big Sky, recorded with vocalist Audrey Gallagher, who was formerly in the 1990s alt-rock band Scheer.

Releases and labels

Much of his work is released on Discover, the British label founded by John Askew. More recent releases appear on Armada Music sub-labels, especially Armind and Soundpiercing. His discography includes numerous singles, a live album, Discover "Live As" Volume 2, and artist albums such as Something To Live For and Never Fade Away.

Notable tracks and recognition

The Agnelli & Nelson remix of his vocal trance track Big Sky is voted “Tune of The Year” by listeners of Armin van Buuren’s A State of Trance radio show in 2007. Big Sky also appears on Never Fade Away. He enters the DJ Mag 100 in 2008 at number 60.