Dafeldecker was born in Austria in 1964 and studied contrabass at the Vienna Conservatorium. He has since focused on European modern music and improvisation, the examination of graphical notations, Fluxus, minimal music, electro-acoustic music, jazz, and field recordings. He has worked with a range of artists including Christian Fennesz, Wayne Horvitz, Tony Buck, Jimmy O’Rourke, Radu Malfatti, Kevin Drumm, and Uli Fussenegger, and has founded the avant-garde label Durian Records in 1995.

With Christian Mühlbacher he created Diphtongs: compositions of a virtual group created from pre-recorded solos by Radu Malfatti, Michael Moser, Burkhard Stangl, and others. He is also a member of a trio with Lawrence English and Scott Morrison.