Ad Delleman worked as an assistant for demographic structural research in Dutch New Guinea from 31 August 1959 to 20 September 1962. The research was financed by the development fund of the European Economic Community. He stayed on Biak and Soepiori in various places in 1959 and 1960. In 1961 he moved to Noemfoor, then to Noeboeai in the Waropen, later to the Padaido Islands and in late 1961 and early 1962 to Nimboran. Later in 1962 he moved to Kokas, Fak-Fak and Mindiptana. On 16 September 1962 the research was terminated because of the transfer of West Papua to the United Nations and Indonesia. On 1 October 1962 he left West Papua. He had already been charmed by sound recording. When going to West Papua he bought himself a tape recorder and started recording over in West Papua as a true sound hunter. He had problems with the recorder, that malfunctioned with the engine rubbing against a part producing unwanted sounds, and running too slowly and with an erratic speed. So, some of his recordings nowadays run too fast and with a too high and variable pitch. In time, he obtained a new tape recorder and he continued to record all kinds of music and events, some of which are quite rare, such as the early string band songs from Noeboeai in the Waropen and the Islamic music and ceremonies from the Kokas area. His recordings were partly broadcast by the RONG in their Dutch and Indonesian broadcasts.