California native Robert Rich is a crucial figure in the development of experimental electronic and ambient music ranging from ethno-fusion and environmental to dark ambient and space music. His early 1980s all-night sleep concerts led to later performances in unconventional spaces, including caves, cathedrals, and galleries. His work reached a wider audience with the 1989 release of Rainforest, which combined natural sounds with electronic drones and exotic instrumentation, set apart by Rich's use of just intonation. He released several well-received collaborations during the '90s, including the 1995 dark ambient classic Stalker (with B. Lustmord), in addition to warm, organic solo efforts like the Arabic-inspired Seven Veils (1998). His 21st century work has ranged from the "lost ritual music" of the acoustic Temple of the Invisible (2003) to the richly textured kinetic electronics of Filaments (2015) and intricate microtonal patterns of Neurogenesis (2020).