Deepening of the voice of people as they reach puberty
A voice change or voice mutation, sometimes referred to as a voice break or voice crack, commonly refers to the deepening of the voice of men as they reach puberty. Before puberty, both sexes have roughly similar vocal pitches, but during puberty, the male voice typically deepens an octave. A similar effect is a "voice crack", during which a person's voice suddenly and unintentionally enters a hig... Wikipedia