Sound, then, is formed by a triple agent--projective, vibrative and reflective.
The lungs are the soliciting agent, the larynx is the vibrative agent, the mouth is the reflective agent. These must act in unison, or there is no result. The larynx might be called the mouth of the instrument, the inside of the mouth the pavilion, the lungs the artist. In a violin, the larynx would be the string, the lungs the bow, the mouth the instrument itself.
The triple action of these agents produces phonation. They engender sounds and inflections. Sound is the revelation of the sensitive life to the minutest degree; inflections are the revelation of the same life in a higher degree, and this is why they are the foundation and the charm of music.
Such is the wonderful organism of the human voice, such the powerful instrument Providence has placed at the disposal of the orator. But what avails the possession of an instrument if one does not know how to use it, or how to tune it? The orator, ignorant of the laws of sound and inflection, resembles the debutant who places the trumpet to his lips for the first time. We know the ear-torturing tones he evolves.
The ear is the most delicate, the most exacting of all our senses. The eye is far more tolerant. The eye resigns itself to behold a bad gesture, but the ear does not forgive a false note or a false inflection. It is through the voice we please an audience. If we have the ear of an auditor, we easily win his mind and heart. The voice is a mysterious hand which touches, envelops and caresses the heart.
Of the Voice in Relation to Compass.
All voices do not have the same compass, or the same range. By range we mean the number of tones the voice can produce below and above a given note on the staff, say A, second space of the treble clef.
There are four distinct kinds of voices: Soprano, alto, tenor and bass. There are also intermediate voices, possessing the peculiar quality of the kind to which it belongs, for example: Mezzo-soprano, with the quality of the soprano and only differing from the soprano in range, the range of this voice being lower than the soprano and a little higher than the alto. Then comes the alto or contralto.
In the male voice we have the tenor robusto, a little lower than the pure tenor and more powerful; next the baritone, a voice between the tenor and bass, but possessing very much the quality of the bass.
The tones in the range of every voice can be divided into three parts--the lower, medium and higher. Thus we would say of a performer, he or she used the lower or higher tones, or whatever the case may be. This applies to every kind of voice.