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 length, with the result that the average adult male voice is about an octave lower in pitch than the female.

The Voice in Music

Not only is the voice the principal means of human communication, but it was undoubtedly the first musical instrument. The principal difference between singing and speaking is that in singing the vowel sounds are sustained and given definite pitch. Despite the innate and natural quality of singing, the training of the singing voice for artistic purposes is among the most subtle and difficult branches of music pedagogy. The instrument is within the performer, and the condition of the vocal apparatus, and thus the quality of the voice, is strictly dependent on the physical and mental condition of the singer. Since the vocal impulse cannot actually be described, the teacher's task is to provide the pupil with concepts, usually systematized into a vocal "method," that will free the vocal apparatus from restrictive tensions and lead ultimately to the complete coordination of all the faculties involved. The foundation of the scientific study of the voice was laid in the middle of the 19th cent. by Manuel Patricio Rodríguez García, a successful voice teacher and writer, who invented the laryngoscope (used to examine the interior of the larynx).

Because of the great changes that have taken place in the art of singing within Western musical culture, modern singers can only approximate the vocal timbre of previous eras. Gregorian chant may have been sung with a nasal timbre resembling Oriental technique. The Neapolitan operatic school developed the virtuoso art of bel canto, in which brilliance of vocal technique was stressed rather than romantic expression or dramatic interpretation. The sound of the castrato (see eunuch), for which many 17th- and 18th-century soprano and alto roles were intended, is approached by several contemporary countertenors using falsetto techniques. The electronic microphone has, in recent times, had an enormous impact on the voice and on styles of singing, through its ability to project very quiet, intimate sounds, and to magnify exciting sounds to a feverish intensity.

Singing voices are classified according to range as soprano and contralto, the high and low female voices, with mezzo-soprano as an intermediate classification; and as tenor and bass, the high and low male voices, with baritone as an intermediate classification. Within these ranges there are specific designations of the quality of a voice, e.g., coloratura soprano. Choral music generally requires a range of about an octave and a half for each voice; a solo singer must have at least two octaves, and some have been known to possess ranges of three, even three and a half, octaves. See also song.

voice, grammatical category according to which an action is referred to as done by the subject (active, e.g., men shoot bears) or to the subject (passive, e.g., bears are shot by men). In Latin, voice is a category of inflection like mood or tense. In ancient Greek, verbs were conjugated in three voices: active, passive, and middle (reflexive).

middle voice, in grammar: see voice.

Voice of America, broadcasting service of the United States Information Agency, est. 1942. Originally set up as a means of fighting the cold war, the Voice of America produces and broadcasts radio programs in English and foreign languages to other countries in order to promote a favorable impression of life in the United States. Programming includes news reports from correspondents on the scene and analysis of events from Washington, D.C., presentation of conflicting views on topical issues, feature programs, and music. The Voice of America, WORLDNET television services, and the Office of Cuba Broadcasting (Radio Martí and TV Martí) are overseen by the International Broadcasting Board of the United States Information Agency.

or voice box

Hollow, tubular structure connecting the pharynx with the trachea, through which air passes on the way to the lungs. The larynx consists of a framework of cartilage plates, with a ridge in front (Adam's apple); the epiglottis, a flaplike projection up into the throat that covers the airway during swallowing to keep food and liquid from entering; and the vocal cords, whose vibration produces the sound of the voice (see speech).

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In grammar, the form of a verb indicating the relation between the participants (subject, object) in a narrated event and the event itself. English grammar distinguishes between the active voice (“The hunter killed the bear”) and the passive voice (“The bear was killed by the hunter”). In the active voice, the emphasis is on the subject of the active verb (the agent performing the action named), whereas the passive voice indicates that the subject receives the action.

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Radio broadcasting network of the U.S. government. Its function is to promote understanding of the U.S. and spread democratic values. Its daily broadcasts include news reports, editorials, and discussions of U.S. political and cultural events. Its first broadcast, in German, took place in 1942 to counter Nazi propaganda. By the end of World War II, it was broadcasting 3,200 programs in 40 languages every week. During the Cold War it focused its message at the communist countries of eastern and central Europe. It became part of the U.S. Information Agency when that agency was formed in 1953.

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