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With reference to the voice, the most important part of the larynx is the vocal bands. They are the chief sound producers. The false vocal cords lie above the true cords. They fold over the latter in coughing, swallowing, etc. The vocal cords are attached to the arytenoid cartilages which move freely on their base, swivel-like, and the movements and tension of the vocal cords are produced by adjustments of these cartilages. The hyoid bone is at the top of the larynx. It has no definite function in sound production except as it affords attachment for the muscles of the tongue.
The glottis is the chink or opening between the true vocal cords.
The tongue is a very important organ in phonation and articulation. Its wonderful ability of adjustments in shape and position in the mouth cavity determines the greater number of modifications of tone resonance.
The uvula is the small curtain which closes the back of the mouth. It and the soft palate determine the direction the breath takes when it comes from the pharynx. If dropped, the air goes partly through the nose, as in sounding the letter “m." If raised, very little passes through the nose. Snoring is caused by the vibration of this curtain.
The teeth, hard and soft palates, and the lips modify the resonance and aid materially in phonation.
In comparing the voice to a single reed-pipe of a church organ, three general analogies are noted: I. A box or windchest into which the air is forced by the bellows; II. A reed or vibrator which is the source of the sound; and III. A resonator, or resonance chamber, aiding in modifying the volume and quality of the sound.
The air is pumped into the wind-chest of the organ and as it meets resistance, it is under considerable pressure. The only outlet is through the narrow slit between the edges of the vibrator or "reed." The air, in passing between the free edges of the vibrator, causes these edges to oscillate in such a manner that they open and close this narrow slit at
regular intervals; thus transmitting to the surrounding air a series of sound waves of the same frequency. The air chamber or resonator above the "reed," by virtue of its resonating property, favors those vibrations that are adaptable to the size of the hollow interior. Those vibrations that are favored are re-enforced; those that are not, are suppressed. Each pipe of the organ is so constructed as to favor, or harmonize the vibrations of its own "reed."
In the human body the lungs act as the wind-chest. Air is drawn into them and placed under pressure. escape only through the narrow slit between two elastic tissue membranes-the vocal cords-which form the "reed" of our vocal machinery. The free elastic edges of these cords vibrate and communicate these waves to the air chamber above them in the same manner as the "reed" of the organ transmits the sound to the resonator.
of the voice is the throat, mouth, and nose.
So far there is a great similarity between the single reedpipe of the organ and the human voice mechanism. Some of the differences must now be noted: 1. The vibrator in the organ always produces the same vibrations; the vocal cords can be regulated at will to perform the function of many organ "reeds." 2. The resonator of the organ is as unchangeable as its vibrator. The resonating chamber in the human voice is adjustable and with proper care may be made to re-enforce, modify and harmonize the sound waves of all the minute shades of tones produced by the vocal cords, normally ranging through two octaves.
The human voice may be compared, in effect, to the entire church organ. Though the range of pitch is not so great, the voice is capable of an infinitely greater variety of vibrations and character of tone within its limited range. It is claimed that Madame Mara, within her range of three octaves, could produce 2100 changes of pitch, which would represent a successive change in the length of the vocal bands of approximately 1/17000 of an inch.
CONTROL OF THE VOICE. The production and control of vocal sound is a very complex process. The ability to coordinate this complicated apparatus, more delicate than any instrument ever manufactured, capable of producing incalculable modulations; so attuned that it responds automatically and unconsciously to our mental perception,demands our utmost care and attention.
First of all, it must be observed that this complex machinery is co-ordinated by the nervous system. Parts are under direct control of the will and parts are involuntary. This complex machinery must be made to respond to our mental percepts, that is, to the ideas we have to be expressed. Without a definite, conscious effort this complex mechanism must respond to our wishes. Hence, (1) definite mental images and proper sound-perceptions develop; (2) the capacity and conscious control of the breath; and (3) control of the vocal cords, resonance mechanism and other organs of articulation; and (4) the harmonious involuntary adjustment of all these processes.
BREATHING. Voice is vocalized breath. In ordinary breathing we inhale and exhale the breath with approximate regularity. In reading or speaking, however, we inhale quickly and exhale slowly, converting the exhalations into vocal sounds. Now, as a fundamental prerequisite in the use of the voice, we must learn to perform properly this inhaling and exhaling process. How often do we hear people who gasp for breath while talking, or who "get out of breath" before finishing a clause or sentence. There is lacking either sufficient breath-quantity, or breath-control, or both. The proper management of the vocal organs requires that the voice have due support and control. This involves the necessity of deep breathing.
There are three ways of breathing whereby the chest capacity is enlarged and the lungs filled with air: Clavicular, or collar-bone breathing; costal, or rib breathing; and
diaphragmatic, or abdominal breathing.
In clavicular breathing, the upper ribs are raised, the breastbone is thrust forward, and the shoulders and collarbones are elevated. By this method, only the upper part of the lungs is inflated; but the exclusive use of this method (which may sometimes be required temporarily by disease and permanently by tight lacing), is as bad for the voice as it is for the health. In the first place, proper vocal support is lacking. The lungs in this kind of breathing can be filled only partially, and hence there is not sufficient reserve supply of air to produce a sustained tone. Secondly, it prevents vocal control. As the shoulders and collar-bones are forced upward, they press against the vocal organs, causing a constriction of the throat; this necessitates an attempt to control the breath in the throat, which was never intended for such purpose; and this, in turn, causes the breath to come in spurts, making the voice trembly, jerky, wheezy, or "throaty." It rasps the vocal cords, and often results in a huskiness known as "clergyman's sore throat."
In costal, or rib breathing the lower or floating ribs are distended sideways, employing the middle portion of the lungs in breathing. This method provides a larger cavity than does clavicular breathing, and thus makes it possible to produce a fuller, rounded, and more sustained tone. It should be employed in connection with the lower portion of the lungs, or deep breathing.
In diaphragmatic or abdominal breathing, the diaphragm contracts, moves downward, while at the same time the abdominal muscles expand the lower chest laterally, thus creating a large cavity for the air to enter. This is the method of breathing that the singer or speaker must adopt. Deep breathing is absolutely essential for a strong, pure, resonant, sustained tone. It furnishes a reserve supply of air for a sustained tone. It allows the throat freedom for proper relaxation and control. It permits one to control the voice from the diaphragm, and this is frequently necessary, as in
ringing, dynamic utterance.
Physicians and writers on hygiene have shown, from statistics carefully compiled, that comparatively few persons breathe correctly; that is, so manipulate the diaphragm that the breathing apparatus is used in the way best suited to physical development.
Do you use the lower part of your lungs in breathing? If not, you should learn to do so, for the muscles controlling respiration are both involuntary and voluntary, that is, we can by conscious attention acquire the habit of deep breathing. In forming this habit, give primary attention to the diaphragm, and the rib breathing will take care of itself; think of filling the lower part of the lungs. Place the hands above the hips, press firmly as you inhale, and you can soon discover whether or not you are using the diaphragm in breathing.
RESPIRATORY CO-ORDINATION. The delicate adjustment of mental-perception, breath-control, and the voice mechanism, must not be overlooked in cultivating a good speaking or singing voice. Mental attitude has much to do with this adjustment.
The amount of air which can be forced into the lungs is estimated ordinarily as 330 cubic inches. The quantity used in quiet respiration is about 30 cubic inches. This is called tidal air. The quantity that can be added to this by taking a deep breath is about 100 cubic inches. This is called complemental air. The quantity that can be expelled by a forceful expiration is about 100 cubic inches. This is called supplemental air. The quantity that cannot be expelled at all is about 100 cubic inches, and is called reserved air.
One very important fact that should always be borne in mind is that all reading and speaking should be done with at least 200 cubic inches of air in the lungs. This demands frequent inhalations while speaking. When shall you take