Your speaking Voice is made up of muscles, cavities, tissues and nerves. It can produce at least 325 different pitches. There are more nerves in the muscles of the larynx than any other muscles in your body. In addition, you use three quarters of your body when you speak a word, e.g even a stubbed toe can affect the sound of your voice. Hence, your voice can be adversely affected by various emotions: excitement, anger, pain, sadness & stress.