Harold Schellinx was one of the initiators of the Dutch ULTRA movement, which provided a common denominator as well as an infrastructure (closely linked to the Amsterdam squatting scene) for the large group of artists and musician that together made up the Dutch brand of experimental post-punk pop music in the late 1970s and early 1980s, and a long time promoter of the world-wide DIY music and cassette culture scene. He studied formal music and computer-aided composition at the Utrecht Institute of Sonology, and mathematics at the University of Amsterdam. His more recent endeavours include dada-ist music & new media-art produced under the monikers of Stduio and ookoi, the Found Tapes Exhibition (exploring and mapping magnetic audio tape litter found in the streets since 2012) and a large number of speculative (‘experimental’) music collaborations, recently most notably in the context of the ongoing series of 'unPublic' performances and recordings (since 2013, see http://unpublic.soundblog.net and http://unpublic.bandcamp.com).
He has been living and working in Paris since 1991.