Noise

NASA researchers at Glenn Research Center measuring aircraft engine noise in 1967

Noise is unwanted or harmful sound considered unpleasant, loud, or disruptive to hearing. From a physics standpoint, there is no distinction between noise and desired sound, as both are vibrations through a medium, such as air or water. The difference arises when the brain receives and perceives a sound.[1][2]

Acoustic noise is any sound in the acoustic domain, either deliberate (e.g., music or speech) or unintended. In contrast, noise in electronics may not be audible to the human ear and may require instruments for detection.[3]

In audio engineering, noise can refer to the unwanted residual electronic noise signal that gives rise to acoustic noise heard as a hiss. This signal noise is commonly measured using A-weighting[4] or ITU-R 468 weighting.[5]

In experimental sciences, noise can refer to any random fluctuations of data that hinders perception of a signal.[6][7]

  1. ^ Elert, Glenn. "The Nature of Sound – The Physics Hypertextbook". physics.info. Retrieved 2016-06-20.
  2. ^ "The Propagation of sound". pages.jh.edu. Retrieved 2016-06-20.
  3. ^ "What's The Difference Between Acoustical And Electrical Noise In Components?". electronicdesign.com. 2012-10-03. Retrieved 2016-06-20.
  4. ^ Richard L. St. Pierre, Jr.; Daniel J. Maguire (July 2004), The Impact of A-weighting Sound Pressure Level Measurements during the Evaluation of Noise Exposure (PDF), archived (PDF) from the original on 2022-10-09, retrieved 2011-09-13
  5. ^ "RECOMMENDATION ITU-R BS.468-4 – Measurement of audio-frequency noise voltage" (PDF). www.itu.int. International Telecommunication Union. Archived (PDF) from the original on 2022-10-09. Retrieved 18 October 2016.
  6. ^ "Definition of NOISE". www.merriam-webster.com. Retrieved 2016-06-20.
  7. ^ "noise: definition of noise in Oxford dictionary (American English) (US)". www.oxforddictionaries.com. Archived from the original on June 14, 2013. Retrieved 2016-06-20.