1980
1980 - Bell, Alexander Graham. "On the Production and Reproduction of Sound by Light: The Photophone." American Association for the Advancement of Science 29 (October): 115-136.

Max Neuhaus utilized Alexander Graham Bell’s 1880 Photophone principle to pioneer wireless, infrared-based sound transmission, creating invisible, site-specific auditory zones. This technology allowed sound to function as a sculptural, site-specific medium, offering personal listening experiences in public spaces without traditional, visible speakers.