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Why does faster vocal-cord vibration make a voice sound higher in pitch?

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Uncover the science behind the transformation of sounds into speech — speech Speech is the faculty of producing articulated sounds, which, when blended together, form language.

The pitch of a voice is determined by the fundamental frequency of vocal cord vibration, which corresponds to the number of air pulses produced per second, measured in hertz (Hz).12

When vocal cords vibrate faster, they create a higher frequency of air pressure cycles, which the ear perceives as a higher pitch. This process is governed by the myoelastic theory of voice production, where air from the lungs forces the vocal cords open, and their elasticity causes them to snap shut, creating a cycle.324

The rate of these cycles is influenced by several factors:
* Tension: Increasing the tension of the vocal cords—often through the cricothyroid muscle—increases the frequency of vibration and, consequently, the pitch.15
* Physical Dimensions: Shorter and thinner vocal cords vibrate more rapidly, which is why children and women typically have higher-pitched voices than men.65
* Aerodynamic Forces: The force of glottal closure and the pressure of exhaled air also play roles in regulating the speed of these vibrations.14