Opposed-Action Breath-Control
A curious misapprehension of mechanical processes is contained in the doctrine of breath-control by opposed muscular action. This can best be pointed out by a consideration of the forces brought to bear on a single rib in the acts of inspiration and expiration. One set of muscles contract to raise this rib in inspiration, an opposed set, by their contraction, lower the rib for the act of expiration. In the opposed-action system of breath-control, the action of the rib-raising muscles is continued throughout the expiration, as a check upon the pull in the opposite direction of the rib-lowering muscles. Theoretically, the downward pull is "controlled" by the upward pull. To express this idea in figures, let the expiratory or downward pull on the rib be said to involve the expenditure of five units of strength. According to the theory of opposed-action breath-control, this downward pull would have to be opposed by a slightly less upward pull, say four units of strength.
Thus graphically presented, the fallacy of the "opposed-muscular" theory is clearly exposed. The rib is lowered with a degree of strength equal to the excess of the downward over the upward pull. If the downward pull equals five units of strength, and the upward pull four units, the rib is lowered with a pull equivalent to one unit of strength. Exactly the same effect would be obtained if the downward and upward pulls were equal respectively to twenty and nineteen units, or to two and one units. Further, the result would be the same if the downward pull involved the exertion of one unit of strength, and there was no upward pull whatever. In every case, the actual result is equivalent to the excess of the downward over the upward pull.
In the case of the expiratory pressure of five units of strength being "controlled" by an inspiratory contraction of four units, nine units of strength are exerted, and the same result could be obtained by the exertion of one unit. There is a clear waste of eight units of strength. The power of the expiratory blast is just what it would be if one unit of strength were exerted in an "uncontrolled" expiration. The singer exerts just nine times as much strength as is necessary to effect the same result. This is why the practice of breath-control exercises is so extremely fatiguing.
So far as the effect of the expiratory blast on the vocal cords is concerned, "controlling" the breath has no influence whatever. The vocal cords respond to the effective air pressure; they are not affected in any way by the opposed contractions of the breath muscles. "Opposed-muscular" breath-control is a sheer waste of time and effort.
Probably no particular harm has ever resulted to any singer's throat from the practice of breath-control exercises. But the attempt to hold back the breath has a very bad effect on the singer's delivery. The "breath-control" type of singer is never found in the ranks of the great artists. There is something utterly unnatural about this holding back of the breath, repugnant to every singer endowed with the right idea of forceful and dramatic delivery. The vast majority of the successful pupils of "breath-control" teachers abandon, very early in their careers, the tiresome attempt to hold back the breath. These singers yield, probably unconsciously, to the instinctive impulse to sing freely and without constraint.
But in the ranks of the minor concert and church singers are many who try conscientiously to obey the instructions of the "breath-control" teachers. Singers of this type can always be recognized by a curious impression of hesitancy, or even timidity, conveyed by their tones. They seem afraid to deliver their phrases with vigor and energy; they do not "let their voices out." Frequently their voices are of excellent quality, and their singing is polished and refined. But these singers never give to the listener that sense of satisfaction which is felt on hearing a fine voice freely and generously delivered.
As for the particular fallacy contained in the theory of ventricular breath-control, that must be reserved for a later chapter. Suffice it to say here that this theory disregards the two basic mechanical principles of tone-production,—Pascal's law, and the law of the conservation of energy. The application of this latter physical law to the operations of the vocal organs is considered in Chapter VI of Part III.