Noise has been a common sonic experience since the beginning of history. For a long time, noise was construed as sound of any form, aggregate of sounds, voice, cry, or roar that was voluminous, disturbing, composite, or extraordinary. By the nineteenth century, however, two specific understandings emerged from this generic characterization: noise as irregular and inharmonious sounds that went against the human senses, and noise as annoying sounds of the surrounding that invaded into the public and private spaces and disrupted tranquility. While the idea of noise as discordance and the idea of noise as nuisance intertwined with each other, they came from different historical contexts. The concept of discordance tied to the Western theories of music since Antiquity, especially their preoccupation with harmonious tones and attempts to make sense of such tones with cosmic-numerological or (later on) psycho-physiological reasons. The concept of nuisance had a close relationship with the efforts by governments, local communities, and civic groups to control and “abate” din in urban and industrial settings. Owing to the rise of acoustical and psycho-physiological research on sounds and the increasing severity of clamor as a consequence of urbanization and the Industrial Revolution, these two notions became the dominant subjects of discussions on noise in technical literature and public discourses before the introduction of the sound-reproducing technologies. These two understandings of noise also became the invisible yet important backgrounds when scientists and engineers in the twentieth century dealt with acoustic and informational noise.
