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Hearing which natural frequencies

  1. Jun 30, 2015 #1
    If you pluck a guitar or cello string, the string vibrates at its fundamental and harmonic frequencies. Suppose the 3rd harmonic has the greatest vibrational amplitude out of all the other rung-out natural frequencies.

    Do we still associate the pitch with the fundamental, or will the pitch now be determined by the 3rd harmonic?
  2. jcsd
  3. Jun 30, 2015 #2
    You have to take response curve of the human ears into account. The actual response strength over the frequency for human is proportional to product of ears response curve to spectrum of your musical instrument and highest pitch (peak) is found in this result. You know that peak of the ear response curve towards low frequency as being aged.
  4. Jul 1, 2015 #3


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    Gold Member

    I believe that if you give the ear a set of harmonics, it tends to generate the fundamental itself. Try using a graphic equaliser on some music.
  5. Jul 1, 2015 #4
    Thank you for responding goodphy and tech99.

    In my mind, you should still hear the fundamental frequency as the pitch: The larger amplitude of the 3rd harmonic simply stretches the complex sound wave vertically; it only affects the intensity/perceived loudness, so the overall frequency/pitch of the complex sound wave is unaltered. (I came to this conclusion after graphing y = sin(x) + sin(3x) [the fundamental and 3rd harmonic; same ampltitude] and y = sin(x) + 2*sin(3x) [different amplitudes].)

    Thus, generalizing this, you should always perceive the fundamental frequency as the main pitch. Of course as goodphy said, what you are capable of hearing depends on your age or how well your ear is functioning. So, as you age, your ear will probably be unable to detect the fundamental frequency, and you will perceive the next audible harmonic as the pitch.
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