Every culture has developed its own style of singing. We may recognize specific vocal sound characteristics in the singing of the Chinese, the Japanese, the Indians (of India), various Middle Eastern and African groups, the Spanish zarzuela and the calypso of Trinidad.
The style we may refer to as operatic or classical singing developed in Europe. This style crystallized during the seventeenth century, as operatic music became increasingly complex and demanding. Its particular characteristics are a greatly extended range, especially at the top of the voice, and increased volume and projection. Music in the European tradition has developed highly mechanized musical instruments, capable of great ranges and volumes. In order to keep pace, singers were gradually trained to increase their capacities as well. Singing in Europe and America is now generally divided into classical and popular styles. The main differences at present concern volume. Essentially all singers in the "pop" fields depend upon the microphone as a matter of course. This enables the singers to deliver their message in a conversational or whispered style of great intimacy, as well as in a louder or more dramatic style.
The operatic singer in most cases still depends only on the unamplified voice; therefore the voice must be developed to its fullest capacity of projection. In order to make the large sound needed to fill an opera house without using a microphone, it is necessary that the singer use all the natural resonance of the upper chest cavities, as well as the sinus cavities in the face and head. These natural spaces serve as little amplifying "echo" chambers. The singer must breathe properly and must focus the tone so that the sound travels forward from the mouth. Proper breathing requires using the full capacity of the lungs. As the lungs are filled, they displace the diaphragm. Then, using the strength of the diaphragm, the singer uses the air to vibrate the vocal chords as the air is expelled. This gives the voice maximum projection. Proper breathing is also a major source of the vibrato (Italian, meaning "to vibrate"). All sound is the result of one object making contact with another: the vibrato (or vibrator) in a singer's voice increases the warmth and resonance of the tone, and also allows for accurate tuning.
Operatic voices are categorized according to range:
||Baritone, Bass baritone
||Bass (Basso profundo)
Opera Basics text courtesy of San Diego Opera and Elizabeth Otten.