Grandma Moon Speaks: Human Voice

Topics Covered:

  • How the Human Voice is Produced
  • Lungs, Vocal Cords and Articulators
  • The Frequency Range of the Male and Female Human Voice

Better to remain silent and be thought a fool than to speak out and remove all doubt – Abraham Lincoln

Human Voice Spectogram
The Matrix? Not really. This is the spectogram of the human voice. Image Courtesy: Dvortygirl, Mysid

Probably the sound we are most comfortable with is our own voice. After all, it is what we hear the most during our lifetime.

No two voices are alike. Each voice pattern is like a fingerprint, unique. Your voice counts!

This is how the human vocal system works:

Human voice analogy
Images Courtesy: Matej Bat’ha, Palmer, Alfred T., diamondmountain, Starsh

It starts with the Lungs, and every other part of your body. The pressure is built up and forced through the Larynx, which house the vocal cords. It is the job of the vocal cords to convert this pressure to distinct packets or pulses of sound.

According to the legendary Bernoulli’s principle, if you try to force the same volume of a fluid (air is a fluid) through two pipes of different size, the pipe with the smaller diameter will force the fluid to travel faster. How does this relate to humans?

The male vocal folds are between 17 mm and 25 mm in length, while the female vocal folds are between 12.5 mm and 17.5 mm. The smaller size forces the air to travel faster, and hence increase in frequency. This is why the female voice is higher pitched.

The frequency range for human speech is 75–150 Hz for men and 150–300 Hz for women.

The muscles of the larynx adjusts the vocal folds to fine tune pitch and tone. This sound is ‘mixed’ in the mouth (cheek, palate), tongue and lips to filter out sound that we recognize as speech or song (or pain). These workers are called Articulators.

It is the ability of the vocal folds and articulators to change size, shape and strength why we are capable of producing highly intricate arrays of sound.


  • Human voice is produced by the lungs, the vocal cords and the mouth, each with the ability to vary the sound pressure and characteristics.
  • The frequency range for human speech is 75–150 Hz for men and 150–300 Hz for women.

Links for further study:

Next: Coming Soon
Previous: Stereo Sound