His music uses a wide range of instruments that can produce such sounds, particularly strings (and, in the opening work, the human voice) as well as his “hexaphonic” electric guitar and the quanûn, in fact two quanûns, the second a microtonal instrument devised by Frenchman Julian Jalâl Eddine Weiss. This quanûn uses a system of 15 accidentals based on a Pythagorean system in each of its strings. Pretty out-there stuff!