voice sound produced by living beings. The source of the sound in human speaking and singing is the vibration of the vocal cords, which are inside the larynx , and the production of the sounds is called phonation. The vocal cords are set into vibration by air from the lungs that moves through the windpipe passing over them, and they in turn produce resonance in the column of air enclosed by the pharynx. The mouth and throat are variable in size and shape, thus permitting alteration of vowel sound and pitch . At puberty the vocal cords of the male become approximately double their original... Read more