Production: Since making his first moves into music production just 5 years ago, John’s notched-up over 20 releases on some of the most respected labels in the industry, prompting Paul Van Dyk to mark him “one of the most exciting producers in the world today”. Club killers like ‘The Chamber’, ‘Exactly’ & ‘Space & Time’ have all become mainstays of DJs sets on many revered trance imprints. In 2007 he released both his first compilation ‘Live As Vol.2’ and his debut artist album ‘Something to Live For’ through Discover Records. Later the same year, in collaboration with vocalist Audrey Gallagher, John produced ‘Big Sky’… By virtue of a 4-month-long club & radio hammering from the big 5, it was voted the No.1 trance tune of 2007 on Armin’s A State of Trance. ‘Big Sky’ has rapidly gained modern trance classic status, virtually taking on a life of its own. John also produces through a number of pseudonyms, including Joint Operations Centre and J.O.C. Under the latter he indulges his love of techno-fringed productions, releasing ‘Rotterdam’ on Sander van Doorn’s own ‘Doorn Records’. In 2008 John was called upon by Godskitchen to mix their Australian 10th Anniversary Compilation, closely followed by ‘Trance World Vol. 4’ which was released through industry giants Armada. John occasionally also collaborates with other select artists, most recently and significantly with trance-legend Giuseppe Ottaviani on the hugely-received VANDIT release ‘Our Dimension’. The spring of 2009 will see the release of John’s highly anticipated 2nd artist album on Armada Records.
DJ: John caught his first DJing break playing on national Irish radio station 2FM’s ‘Sessions Tour’, which was broadcast on New Years Eve, 2003. He has gone on to throw trance-fire onto the floors of some of the world’s highest-profile clubs and festivals. Counted amongst them are Ireland’s Planet Love, Global Gathering, Trance Energy, WMC Miami, South America Music Conference and Creamfields, amongst others. 2008 went down as John’s all-important DJ breakthrough year... One that saw him play 6 nights on the White Isle, including Judgement Sunday & Armada at Amnesia, before going on in October to conquer Australia as part of Godskitchen’s infamous yearly nationwide tour. Latterly, O’Callaghan has expanded his fan-bases in Poland, The States, Argentina, Mexico, Canada, Slovakia and The Czech Republic – territories which he credits as being the deciding factor in entering the 2008 DJ Top 100 chart. In Utrecht in March of 2009 John will play the main-stage at Trance Energy – now widely regarded as the pinnacle apex of the trance calendar, a colossal accomplishment for the Irish virtuoso.
The Subculture Radio Show: For the last two years John has presented his take on the trance scene, via his Subculture show on widely popular station, DI.FM. Subculture presents a crystal-clear monthly snapshot of John’s in and out of club sound, exploring the outer reaches of electronic music. The show goes out at 5pm UK time on the 2nd Monday of the month, noon US EST and 6pm CET.
Remixes: Although his studio career carries more of an original production bias, John has lent his musical skill to many exceptional remixes. In 2005 his debut came in the form of the hugely-received rewiring of fellow countrymen Agnelli & Nelson’s ‘Shiver’. From there he went on to rework Dogzilla’s ‘Without You’, Ronski Speed's 'The Space We Are' & Filo & Peri's 'Anthem', amongst others. So taken was Armin by John’s 2008 remix of ‘If You Should Go’ that he took the rare step of asking O’Callaghan to rework a second track from his ‘Imagine’ album. John’s remix of The Doppler Effect’s ‘Beauty Hides in the Deep’ last year became a cult hit within the trance fraternity and is regularly sited as his greatest remix to date. He is widely regarded as one of the most in-demand producers & remixers in electronic dance music today.