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The sound of a perfect square wave

  1. Feb 18, 2015 #1
    Hey guys,

    It is stated that a 100% perfect square shaped wave have infinite odd harmonics and it is impossible to produced theoretically. But, assuming if a perfect square wave is produced, what would it sound like? I remember someone said it in Youtube it would actually sound like a clarinet instead sounding harsh and buzzy.
  2. jcsd
  3. Feb 18, 2015 #2

    Vanadium 50

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    It's a common alarm tone, and you can hear one yourself on the Wikipedia article on square waves.
  4. Feb 18, 2015 #3


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    Human ears can't hear anything above about 20 kHz*, so you couldn't hear the difference between a "perfect" square wave and one with harmonics above 20 kHz removed.

    *That's for healthy young ears. The limit could be much lower for older ears.
  5. Feb 18, 2015 #4


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    In addition to the limitation of human hearing, wouldn't the air also limit the ramp rates on something close to a generated square wave?
  6. Feb 18, 2015 #5
    One fun thing you can try if you have access to Mathematica is to find the Fourier series for a square wave and then use the 'Play' function. You can add successive harmonics and try each one and then experience it for yourself.
  7. Feb 20, 2015 #6
    Thanks for the response. But recently I hear people saying that ultrasound can be heard if it is fed directly to the skull, I think it doesn't sound like any of the musical notes for example, the highest note of the piano. I think it sounds weird and unique. Thoughts?
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