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The seventh upper partial is three octaves above the prime, with eight times the number of vibrations.
Many other partials occur in some compound tones, but always in the same relative position.
Simple tones have a very soft, pleasant sound, free from all roughness, but wanting in power, and dull at low pitches."
“Musical tones, which are accompanied by a moderately loud series of the lower upper partial tones up to about the sixth partial, are more harmonious and musical. Compared with simple tones they are rich and splendid, while they are at the same time perfectly sweet and soft if the higher upper partials are absent.”
“If only the uneven partials are present, the quality of tone is hollow; and when a large number of such partials are present, it is nasal. When the prime tone predominates, the quality of the tone is rich or full; but when the prime tone is not sufficiently superior in strength to the upper partials, the quality of the tone is poor or empty.
“When partial tones higher than the sixth or seventh are very distinct, the quality of the tone is cutting and rough. The degree of harshness may
very different. When their force is inconsiderable, the higher upper partials do not essentially detract from the musical applicability of the compound tones ; on the contrary, they are useful in giving character and expression to the music.”
Tuning-forks are the most difficult to set in sympathetic vibration. To effect this they must be fastened on sounding-boxes which have been exactly tuned to their tone. If we have two such forks of exactly the same pitch, and excite one by a violin bow, the other will begin to vibrate in sympathy, even if placed at the farther end of the room, and it will continue to sound when the first is damped. The astonishing nature of such a case of sympathetic vibration will appear, if we merely compare the heavy and powerful mass of steel set in motion with the light, yielding mass of air, which produces effect by such small motive power that it could not stir the lightest spring which was not in tune with the fork. With such forks the time required to set them in full swing by sympathetic action is also of sensible duration, and the slightest disagreement in pitch is sufficient to produce a sensible diminution in the sympathetic effect. By sticking a piece of wax to one prong of the second fork, sufficient to make it vibrate once in a second less
than the first, a difference of pitch scarcely sensible to the finest car, the sympathetic vibration will be wholly destroyed.” 1.
Thus sympathetically the chambers of the pharnyx, ventricles, nares, mouth – the entire vocal passage, chest, and head - re-enforce the tones of the vocal bands.
Vowel-resonance. One vowel sound is distinguished from another, though both have the same pitch and intensity. This fact was long a question of inquiry. Sir C. Wheatstone first stated the true theory, which was afterwards subjected to exhaustive study by Helmholtz. “ The vibrations of the vocal bands associate with the vibrations of the resonant cavity of the mouth, which can so alter its shape as to resound at will either the fundamental tones of the vocal cords or any of their overtones. With the aid of the mouth, therefore, we can mix together the fundamental tone and the overtones of the voice in different combinations.” Helmholtz was able to imitate those tones by tuning-forks, and by combining them appropriately to produce the sounds of the vowels.
I once had the pleasure of seeing Mr. Alexander Graham Bell exhibit the fact that vocal pitch may be determined by the shape of the mouth cavity. Closing the mouth, and moving the tongue to alter the shape of the cavity to suit, the pitches of the scale were distinctly produced by snapping a lead-pencil placed against the windpipe.
For practical purposes we distinguish the chest from the head resonance. The former is brilliant, clear, and ringing; the latter is full and mellow. Chest resonance is due to the actual sympathetic vibrations of the chest; while the head resonance is due to the resonance of the face and head. Some voices use more of one than of the other, while some combine the two for the ordinary voice. The varied use of resonance is determined by the kind of emotion to be expressed.
Vocal Defects. — Besides defects resulting from natural limitations and disease, there are others due to a lack of skill in the use of the organs. The latter are removable, and the accomplishment of this forms an important part
1 Sensation of Tone. Helmholtz.
of the minor problem of Public Speaking. They may be described as follows:
1. Squeezed-back voice. This is the guttural voice, and results from an attempt to manage the voice by means of the throat muscles, rather than by use of the deep respiratory muscles.
2. Fall-back voice. This results from a failure to continuously support the voice. Instead, it allows it to fall back in the throat; and it is slightly squeezed, especially at pauses.
3. Back-back voice. This is the voice improperly “focused.” It is held far back in the pharynx. It lacks support and projection, and sounds muffled, feeble, and far off. An over-cautious use of the voice in case of a sore throat generally exhibits this quality.
4. Nasality, resulting from lowering the soft palate and uvula, and allowing the voice to beat against them instead of freely passing to the front part of the mouth, is a most common fault.
5. Thick or mouthful voice, resulting from carrying the tongue too high, and attempting to articulate with the top instead of with the tip of the tongue.
6. Huskiness, resulting from thickened vocal cords, and from allowing non-vocalized breath to escape because of a faulty adjustment of the vocal cords.
Besides the causes assigned to the several faults named, the habit of running too long on one breath is the frequent accompaniment of husky, feeble, and squeezed voice.
Vocal Development. - In analyzing the leading faults of voice, it will be found that they are due either to a failure to support and control the voice by means of the diaphragmatic and other deep respiratory muscles, or to an improper obstruction of the vocal passage at some point, or to both. It will be found, moreover, that the qualities of good voice depend upon the reverse; that is, upon a deep support and control, and a relaxed and free condition of the vocal pas
sage. A recognition of these two facts renders simpler our understanding of the main features of vocal development.
Vocal support and control involve deep breathing. The more obvious signs of deep breathing are as follows: While avoiding the sudden lifting of the shoulders and upper part of the chest, and directing the inspired breath to the lower part of the chest or upper part of the abdomen, it will be observed that this part of the body, together with the sides, will be pressed out, and then followed by a slight falling in of the same, and an enlargement of the whole chest. Leading attention, however, is to be given to the deep distention. The following description of respiration, the facts and quotations of which are from Dr. Martin's “ The Human Body," may aid in an understanding of the breathing process:
1. The Enlargement of the Thorax for Inspiration. -(1) The diaphragm is a strong, sheet-like muscle, arching up dome-like, separating the chest and the abdominal cavities. Its muscular fibres radiate from the dome downwards and outwards, and are attached to the breastbone, the lower ribs, and the vertebral column. By contraction the diaphragm sinks to a horizontal position, thus greatly increasing the size of the thorax vertically.
(2) The ribs slope downwards from the vertebral column to the breastbone. “ The scalene muscles, three on each side, arise from the cervical vertebræ, and are inserted into the upper ribs. The external intercostal lie between the ribs, and extend from the vertebral column to the costal cartilages; the fibres slope downwards and forwards."
“During inspiration the scalenes contract, and fix the upper ribs firmly; then the external intercostal shorten, and each raises the rib below it.” Thus the ribs are elevated, the breastbone shoved out from the spine, and the capacity of the thorax enlarged from front back. Other muscles are employed, but chiefly in offering points of resistance to those already described. These are the principal ways of enlarging the chest, and require considerable muscular effort.
Now, when the chest is enlarged, the space between the lungs and sides of the chest forms a cavity which contains no air. The external air, with a pressure of 145 pounds to the square inch, rushes in when the glottis of the air-box is open, distends the lungs, just as an elastic bag suspended in a bottle may be made to distend and touch the sides of the bottle from which the air has been exhausted.
2. Expiration. – In expiration very little muscular effort is required. After inspiration, the muscles relax, and the sternum and ribs fall to their former position. The elastic abdominal wall presses the contained viscera against the under side of the diaphragm, arching it up. Thus the air is sent out in passive breathing most largely by the elasticity of the parts stretched in inspiration, rather than by special expiratory muscles.
In the forced breathing of vocal effort, the muscles of expiration assist in the expulsion of air. “ The main expiratory muscles are the internal intercostal, which lie beneath the external, between each pair of ribs, and have an opposite direction, their fibres running upwards and forwards.” The internal intercostal, contracting, pull down the upper ribs and sternum, and so diminish the size of the thorax from front back.
At the same time the lower ribs and breastbone are pulled down by a muscle running in the abdominal wall from the pelvis to them. “At the same time, also, the abdominal muscles contract and press the walls of that cavity against the viscera, force the diaphragm to arch up, and lessen the cavity from up down."
In violent inspiration many extra muscles are called into play, chiefly as points of firm resistance, or otherwise assisting the usual muscles of inspiration.
In violent expiration, also, many other muscles may co-operate with the usual muscles, tending to diminish the thoracic cavity.
3. Kinds of Breathing. — The breathing that brings the upper part of the chest into the greatest action, and lifts the clavicles or collar bones excessively, is called “clavicular breathing." It is readily seen that the lungs in this kind of breathing can only be partially filled, as the lower part of the chest is still contracted.
When breathing is carried on by action of the ribs, it is then called “costal,” or 'chest-breathing." This, like “clavicular breathing," does not admit of the lungs being fully distended.