The Psychology of Singing / A Rational Method of Voice Culture Based on a Scientific Analysis of All Systems, Ancient and Modern

by David C. Taylor

[CHAPTER IV]

RESONANCE

In order to understand fully the position in Vocal Science assigned to the doctrine of resonance, it is necessary to trace the origin and the development of this doctrine. The old Italian masters naturally knew nothing whatever of resonance, nor of any other topic of acoustics. Yet the accepted theories of resonance in its relation to the voice are directly based on a set of empirical observations made by the old masters. The facts which they noted are now a matter of common knowledge. In singing low notes a sensation of trembling or vibration is felt in the upper chest; high notes are accompanied by a similar sensation in the head. How these sensations of vibration came to be made the basis of the theories of vocal resonance, and of registers as well, is an interesting bit of vocal history.

Although almost entirely ignorant of vocal mechanics in the scientific sense, the old masters were eager students of the voice. They carefully noted the characteristic sound of each tone of the voice, and worked out what they believed to be a comprehensive theory of tone-production. One of their observations was that in every voice the low notes have a somewhat different quality from the high notes. To distinguish these two qualities of tone the old masters adopted the word used for a similar purpose by the organ builders,—register. Further, they noted the sensation of vibration in the chest caused by singing low notes, and concluded that these notes are actually produced in the chest. To the lower notes of the voice they therefore gave the name "chest register." As Tosi explains it, "Voce di Petto is a full voice, which comes from the breast by strength." For a precisely similar reason, viz., the sensation of vibration in the head felt in singing the higher notes, this portion of the voice was called by the old masters the "head register."

When the study of vocal mechanics along scientific lines was undertaken, in the early decades of the nineteenth century, attention was at first paid almost exclusively to the subject of registers. The questions then most discussed were the number of registers, the number of notes which each should include, and the precise point of production of each register in the chest, throat, and head. Garcia's Mémoire, dealing with the registers, was noticed in the preceding chapter. He showed that different adjustments of the tongue, palate, and larynx are concerned in the production of the various registers. This Mémoire opened up a new line of observation, in which Garcia continued to take the lead. But the extending of the scope of inquiry concerning the registers did not result in any unanimity of opinion on the part of the vocal investigators of that time.

For a few years following the invention of the laryngoscope (1855), vocal theorists ceased their disputes about the registers, and awaited the definite results of this new mode of observation. When this potent little instrument was put within the reach of every investigator, it was believed that the mystery surrounding the registers was about to be dispelled.

One important consequence of the invention of the laryngoscope was the turning of attention away from the sensations of vibration in the chest and head. Each register was ascribed to a distinct mode of operation of the vocal cords, and for several years the terms "chest voice" and "head voice" were held to be scientifically unsound. But with the publication of Helmholtz's Die Lehre von den Tonempfindungen in 1863, the sensations of vibration again received attention. These sensations were then made the basis of a theory of vocal resonance, which has since been adopted by the great majority of vocal scientists.

Until the publication of Helmholtz's work vocal theorists had known practically nothing of acoustics. The fact that the tones produced by the vocal cords are increased in power and modified in quality by the resonance of the air in the mouth-pharynx cavity came as a distinct revelation to the theoretical students of the voice. Helmholtz confined his experiments and demonstrations to the mouth-pharynx cavity, and investigated in particular the influence of this cavity in producing the various vowel and consonant sounds. But vocal theorists at once extended the idea of air resonance, and connected it with the well-known sensations of vibration in the chest and head. It was assumed that these sensations are caused by vibrations of the air in the chest and nasal cavities.

This assumption has been accepted without question by the great majority of vocal scientists. Both the chest voice and the head voice are now believed to owe their distinctive qualities to the reinforcing vibrations of the air in the chest and nasal cavities respectively. The mere fact that these vibrations can be felt is held sufficient proof of the statement. "In every true chest tone the resonance can be distinctly felt as a vibration (fremitus pectoralis) by the hand laid flat on the chest." (Die Kunst der idealen Tonbildung, Dr. W. Reinecke, Leipzig, 1906.) It must be observed that this is by no means a satisfactory scientific proof of the doctrine of chest resonance. This feature of the subject is reserved for discussion later.

The doctrine of resonance is now generally accepted as one of the basic principles of Vocal Science. It is stated, in substance, by almost every authority on the voice that "The tone produced by the vibration of the vocal cords, even when the laryngeal action is correct in every way, is weak, of poor quality, and without character. This tone must be strengthened and made of musical quality by utilizing the influence of resonance." The subject of resonance is always treated in theoretical works on the voice under the three heads of chest, mouth-pharynx, and nasal resonance. To these a fourth is sometimes added,—the sounding-board resonance of the bones of the chest and head.