Phase distortion

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In signal processing, phase distortion or phase-frequency distortion is distortion, that is, change in the shape of the waveform, that occurs when (a) a filter's phase response is not linear over the frequency range of interest, that is, the phase shift introduced by a circuit or device is not directly proportional to frequency, or (b) the zero-frequency intercept of the phase-frequency characteristic is not 0 or an integral multiple of 2π radians.


Audibility of phase distortion

Grossly changed phase relationships, without changing amplitudes, can be audible but the degree of audibility of the type of phase shifts expected from typical sound systems remains debated. [1] [2] [3]

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  1. Arthur C Ludwig Sr. (1997). "Audibility of Phase Distortion" . Retrieved 15 February 2016.
  2. Lipshitz, Stanley P.; Pocock, Mark; Vanderkooy, John (1 September 1982). "On the Audibility of Midrange Phase Distortion in Audio Systems". Journal of the Audio Engineering Society . 30 (9): 580–595.
  3. "Human Hearing - Phase Distortion Audibility".

PD-icon.svg This article incorporates  public domain material from the General Services Administration document: "Federal Standard 1037C".(in support of MIL-STD-188)