When you are advised to take candy or anything else for sore throat, for hoarseness, etc., you may know now that such things do not pass through the air tube, but through the food pipe, and consequently cannot help your hoarseness. At the upper end of the air tube and below the hyoid bone is the main part of the vocal organ, or larynx.
For the present, it will be sufficient to say the larynx consists of the two principal cartilages: the lower one is called the “ring” or cricoid cartilage; the upper one, the “Adam’s apple” or the thyroid cartilage. See Nos. 4 and 5. The latter consists of two plates which are joined in front and which form the part so prominent in some men. From the sides of the larynx arise muscles which form the sack-like opening of the throat into the mouth.
This region is called the pharynx. See fig. 42
Back of the pharynx is the esophagus or food pipe. Food enters into the mouth, is ground between the teeth, then enters the pharynx which contracts powerfully over it and forces the food into the food pipe, which contracts and forces the food into the stomach. During this action, the air tube is tightly closed by the means of a special cover called the epiglottis.
The air tube and food pipe have, in common, the upper space of the pharynx, the mouth and the nose. See fig 43.
The head and throat are connected with the upper part of the chest by means of very strong muscles, as shown in Fig. 38:
Underneath these muscles are the muscles of the larynx and hyoid bone. They arise out of the breastbone, except one, which starts from the collar bone. Remember, there are always two muscles, one on each side. Of course, only one can be shown in the same illustration.
However, in Fig. 38, both sides are given.
Now look at the muscle sharked “sth.” This is the stern hyoid muscle because it arises from the breastbone (sternum) ad ends in the hyoid bone. Notice that this pair of muscles leaves a free space between which you can see the larynx (L). They hyoid bone is marked “H”.
The muscle marked “oh” is called the omo-hyoid; it arises out of the collar bone, bends sharply forward, and is fastened to the hyoid bone above. A large part of this muscle is hidden by the one overlapping it. This part of the omo-hyoid lies against the lower part of the larynx, which is a very important point to observe because, as this muscle reaches considerably backward to the collar bone, it will pull the lower part of the larynx strongly against the spine and hold it there very firmly. This gives all the other muscles a fulcrum and greater leverage; greater resonance also is obtainable owing to this fact.
Again, under the first named muscle, there is another marked “stth” (Fig 38), only a part of which can be seen.
This is the sterno-thyroid muscle, and extends from the breatbone to the thyroid cartilage, or Adam’s apple. All these muscles lie in front of the larynx and hyoid bone. When they contract they naturally pull the upper parts downward. As muscles contract they become smaller. They shrink, but, as these muscles are fastened below to firm bones, and above to freely movable bones, they naturally pull the movable bones downward. Because these muscles pull downward, they are classed as muscles “under” the hyoid bone, while those muscles which pull upward are classed as “over” the hyoid bone.
We are simply confining ourselves to the study of those muscles which directly operate the larynx and produce sound, but there are many other muscles which, to some degree, affect the voice, notably the jaw muscles, and these are the strongest of all muscles. Their influence, however, is almost entirely destructive to good voice. Therefore, we must understand these muscles as well. Therefore, in a later lesson, when we learn of false vocal effort, we shall return to these muscles.
You see in the illustrations many muscles that we make no mention of. Most of them have nothing whatever to do with voice, therefore, we ignore them now. They are merely muscles which hold and move the head. It is enough that you can already understand that teacher who tell you to pull the larynx down are very greatly in the wrong, because pulling the larynx down does not stretch the vocal chords, and makes high and strong tones impossible. The same must be said when you are told to raise the larynx or, what amounts to the same, the palate, hence, merely raising the larynx does not stretch the vocal chords either, and makes strong tones impossible.
In ordinary conversation, where the words are spoken lightly or at least with no special power, the vocal chords do not need to be stretched or tensed to a strong degree. But for public speaking and still more for singing, when the tone is many times more powerful, they must be very strongly stretched, not only for the high tones, but for the middle and low tones as well, in order to give the vocal chords the great size required for heavier power. This dependence of power and also quality, as well as pitch, upon the tension or stretching of the vocal chords will soon be explained. For the present you must take it for granted.
If the larynx is allowed to rise, the up-pulling muscles are, or course, much shortened, and all the down-pulling ones are much lengthened. If the larynx sinks, all the down-pulling muscles are shortened and the up-pulling ones lengthened. Either of these positions implies a weakening of either the up-pulling or down-pulling muscles for it is a well-established law that a muscle loses strength when shortened or lengthened beyond its natural extent.
It is true that a muscle, when contracted, shortens a little, but this is more of a tensing effort where the muscle merely takes up its slack and becomes firm and tense. On the other hand, a muscle should never be lengthened beyond its natural size. Just as a string, when it is being pulled beyond its length, may break, so a muscle may be strained and lose its power and efficiency. These points should be remembered for they are valuable, not only for the training of the vocal organ proper, but also for breathing, when we come to that part of the instructions.
For now, just knowing all the muscles which pull the larynx downward now, we must learn about the muscles which pull the larynx upward, so that the vocal chords inside of the larynx can be stretched. Keep in mind, also, that an upward pull is necessary, if the down-pulling muscles are to have a hold or brace against which they can use their full power.
The muscles above the hyoid bone extend from the hyoid bone to the chin, the tongue, the palate and the skull, as is shown in Fig. 44. (See No. V, Hyoid Bone.)
In No. 1 are shown the biventer mandiulae muscles. Some physiologists call them the digastric muscles. They consist really of two muscles, joined together near the hyoid bone by a tendon. They start in the skull or cranium and extend downward and forward to fasten upon the inner side of the chin. They connect with the hyoid bone by a broad band or tendon. This is one of the most mischievous of the interfering muscles, because it can cause trouble in so many ways. It can pull the hyoid bone strongly upward, or it can pull the bone and the entire larynx strongly forward. This muscle causes the choked, loud sound sometimes noticed by singers.
The mylo-hyoid muscles is show by No. 11. If you touch the lower jaw inside and under the tongue as far as the teeth extend, you will follow the muscle’s line of attachment to the lower jaw. The fiber of this muscle, which starts near the back teeth, reaches downward to the front part of the hyoid bone, and can do considerable harm by drawing the bone either upward or forward. This muscle really forms the floor of the mouth. It is sometimes called the diaphragm of the mouth.
This stylo-hyoid muscle is shown by No. III. This is a slender muscle, fastened above to the pen-like projection of the ear bone (stylo-pen) and below to the hyoid bone, where it can assist the first named biventer muscle in its interfering work.
The genio-hyoid muscle is shown by No. IV. This muscle is attached to the inner side of the chin, just above the mylo muscle and below the tongue. It reaches backward and is fastened to the hyoid bone. Therefore, it also can draw this bone forward, with tone destroying effect.
All of these four pairs of muscles are really detrimental to the voice. You may ask, why are they there, and why do we dwell upon them? Well, in the first place, these muscles really belong to the masticating chain of muscles. Nature never intended them for vocal muscles at all. You must remember, however, that the larynx is primarily the organ whereby air is taken into the body. The voice is a secondary activity. All these muscles are closely connected with and assist the tongue in swallowing, and the jaw in masticating food. In these efforts the four muscles mentioned play a necessary part. But many singers and speakers, unfortunately, use the masticatory muscles in singing and speaking. Then these muscles are compelled to do something for which nature never designed them. The result, of course, if serious damage to the voice.
You can easily see now how important it becomes that you should know the right vocal muscles from the wrong ones. Knowing this, you can work intelligently, like a human being, and not like a stupid animal, which does a thing merely because it must.
Knowing these muscles and knowing, at least, the main factors in your organs of voice will help you appreciate and master your subject much better and easier.
Since we now know and understand what muscles are legitimate or voice producing, and what muscles are illegitimate or voice destroying, and why, our study becomes ABSOLUTELY scientifically exact, and just as true and to the point as a mathematical problem.