The first public line-up of the band included Byrd, Moskowitz, Woodson, and two contemporary classical musicians with whom Byrd had worked on earlier experimental projects in the New Music Workshop: Gordon Marron (violin) and Rand Forbes (bass). Later, for some of their recordings and performances, they added Marron's friend and writing partner Ed Bogas (keyboards). Byrd initially commissioned electrical engineer Tom Oberheim to build him a ring modulator, later replaced by electronic oscillators in a monophonic synthesizer built by aerospace engineer Richard Durrett. Among other effects, Marron used an octave divider on his electric violin, and Woodson attached contact microphones to his drum set and hung slinkies from his cymbals for a "musique concrète" effect.