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Can the term distortion be used interchangeably?

  1. Oct 18, 2013 #1
    Can the term "distortion" be used interchangeably?

    Clipped sine wave = distortion

    Assume I run a 30hz tone through one of my dedicated mid-range loudspeakers. There's no doubt that the loudspeaker would bottom out. People often call this distortion. But the signal never clipped. It's the loudspeaker that's distorting.

    I assume distortion can be classified into...?
  2. jcsd
  3. Oct 19, 2013 #2

    Simon Bridge

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    "... interchangeably" with what?

    Anything that is distorted.
    If the signal is not distorted when it arrives at the speaker, then the term "distortion" does not apply to the signal. But the signal response of the output (speaker) may, yet, distort the sound. That is still distortion.

    A clipped signal is only one form of distortion - it's a very broad term.
  4. Oct 19, 2013 #3


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    Distortion means anything different (about the waveform shape) than what you expect wherever you measure it. It can be be amplitude distortion, jitter distortion, aliasing distortion, speaker distortion, frequency response distortion, crossover distortion, whatever. Noise is sometimes considered separately, but not always (noise floor, quantizing noise, whatever).
  5. Oct 20, 2013 #4


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    If you look at the frequency spectrum and the harmonics change in amplitude or phase relative to the fundamental then the signal is distorting.

    If additional frequency components appear that are not harmonics of the fundamental then it is called noise.
  6. Oct 20, 2013 #5


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    I think aliasing artifacts are considered distortion and they are not harmonic. I think you can (these days) expand distortion to include any artifacts that are correlated to the input signal.
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