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Voice Disorders. A voice disorder is when the voice has a problem with pitch, volume, tone, and other qualities. These problems occur when the vocal cords don't vibrate normally. Your voice is the sound that air makes when it is forced out of your lungs and passes over your vocal cords.
Disorders of the voice involve problems with pitch, loudness, and quality. Pitch is the highness or lowness of a sound based on the frequency of the sound waves. Loudness is the perceived volume (or amplitude) of the sound, while quality refers to the character or distinctive attributes of a sound.