The Physiology And Psychology Of Voice-production

Above this chapter I might well have placed the following lines which

George Eliot wrote above Chapter XXXI. of "Middlemarch."

How will you know the pitch of that great bell,

Too large for you to stir? Let but a flute

Play 'neath the fine-mixed metal! Listen close

Till the right note flows forth, a silvery rill:

Then shall the huge bell tremble--then the mass

With myriad waves con
urrent shall respond

In low, soft unison.

The lines telling of the great bell stirred by the note of a flute

played at the proper pitch suggest the moving power that lies in

sympathetic vibration. The first time a military body crossed the

Brooklyn Bridge, the spectators were surprised to hear the order given

for the soldiers to march out of step. They had expected to be thrilled

by the sight of a thousand men crossing the great structure in measured

tread, with band playing and colors flying. They did not know that the

structure, being a suspension bridge, might have been weakened and

possibly destroyed by the force of rhythmic oscillation. Yet the

accumulated force in the tramp of a thousand men is no greater than that

which lies in the sympathetic vibrations of a musical note. Every metal

structure has its note, and it is an old engineering saw that a huge

structure like the Brooklyn Bridge eventually could be destroyed by the

cumulative force of sympathetic vibration evoked by a musical instrument

constantly reiterating the note of the bridge.

Sound has three dimensions: pitch, loudness and timbre.

Pitch depends upon the frequency of vibrations. The more rapid the

vibrations, the higher the pitch.

Loudness is determined by the amplitude of the vibrations. As their

length or "excursion" increases, so does the sound gain in loudness.

Conversely, the diminution in the size of vibrations causes

corresponding decrease of loudness.

Differences in the shapes of vibrations cause differences in quality

or timbre.

After voice has originated within the restricted limits of the larynx,

its power, its carrying quality is much augmented by the sympathetic

vibrations within the resonance cavities above the larynx. These include

the pharynx, nasal passages, mouth, bone cavities of the face--in fact

pretty much every hollow space in the head, every space that will

resound in response to vibration and assist in multiplying it. Moreover,

the cavities of resonance by their differences in shape in different

individuals determine the timbre or quality of individual voices. The

chest, although situated below the larynx, is a resonance cavity of

voice. In fact, in a certain register its vibration is felt so

distinctly that we speak of these notes as being sung in the "chest

register," which, so far as it implies that the tones are produced in

the chest, is a misnomer. The same is true of "head register," in which

vibration is felt in the head where, however, it is needless to say,

the "head tones" do not originate.

Expiration--breath-emission--is the motor function of the vocal organs;

and there are two other physical functions of the organs--vibratory and


Added to these is the sensory function, to which I attach great

importance; and I call it a psychological function because it acts

through the nerves upon the physical organs of voice. Without it the

three physical functions--motor, vibratory and resonant combined--would

remain ineffectual. They could generate voice, but it would be voice

lacking those higher qualities that are summed up in the word

"artistic." It would be a physical, not an art product, a product

generated by the body without the cooperation of the mind or soul. When

it is considered that the larynx, in which the vocal cords are situated,

is permeated by a network of muscles through which it is capable of some

16,000 adjustments and readjustments of shape, all of them pertinent to

voice-production, and that the same thing also is true of the pliable

portions of the resonance cavities; that these muscles act in response

to an even finer network of nervous filament; and that the constant

shaping and reshaping of various parts of the vocal tract during

voice-emission is directed by messages from the mind, soul, or art-sense

of the singer, messages which travel via nerve to muscle--the only route

by which they can travel--it becomes possible to appreciate the

importance of the sensory or psychological function which, I hold,

should be added to the purely physical ones of motor, vibration and

resonance. For by it these functions are enlisted in the service of

art and made immediately and exquisitely responsive to the emotional

exaltation of music and song. Nor are these vague terms. Psychology

of song and psychological action in general may seem indefinite and

unintelligible. They become, however, absolutely definite and

intelligible when the part played by the nerves as intermediaries

between mind and muscular action of a subtle and highly refined order

is appreciated. The mind presses the button, the nerves carry the

messages, and muscle acts instantaneously and responsively.

The student need not despair because so many separate acts seem

necessary to the production of even a single tone. It is true that air

has to be taken into the lungs and emitted from them; that it must be

controlled by the singer as it passes up the windpipe; that the vocal

cords and other parts of the larynx must be given their specific

adjustment for each note; and the cavities of resonance shaped in

sympathetic coordination with those numerous adjustments, while the lips

also have their function to perform. But it is equally true that correct

instruction supplemented by assiduous practice merges all these separate

acts into one. The singer thinks the note, forms what may be called a

sounding vision of it in his mind, and straightway the vocal tract

adapts and coordinates all its parts to the artistic emission of that

note. It is auto-suggestion become habit through practice.

Because the larynx is so important a factor in generating voice,

writers on voice-production have described it with much minuteness,

and because of these minute descriptions readers may have obtained an

exaggerated idea of the size of this organ. But one of the marvels of

voice-production is the smallness of the organ in which voice is

generated, the size of the average larynx being about two inches in

height by an inch and a half in width. Yet so numerous are the

adjustments in shape of which this small organ is capable that the

phenomenal soprano, Mara, could make 100 changes in pitch between any

two notes in her voice, and as this had a compass of twenty-one notes,

it follows that she could produce no less than 21,000 changes in pitch

within a range of twenty-one notes. While in Mara's day this no

doubt was attributed to a natural gift of voice, modern study of

voice-physiology and of the metaphysics of voice-production readily

accounts for it. It needs an ear naturally or by training so

delicately attuned to pitch that not only all the fundamental notes of

a voice, but all the numerous overtones at infinitesimal intervals are

heard in what may be called the singer's mental ear; that the nerves

convey each of these sounding mental conceptions to the intricate

system of muscles in the larynx and resonant cavities and that the

right muscles immediately adjust the larynx and cavities of resonance

to the shape they have to assume to sound the corresponding note.

Every vocal tone is, in fact, a mental concept reproduced as voice by

the physical organs of voice-production, so that every vocal tone is,

in its origin, a mental phenomenon. That is why an inaccurate ear for

pitch results in a vocalist singing off pitch. His mental conception

of the note is wrong, the message conveyed from the mind over the

nerves to the muscles of the vocal organs is wrong, consequently they

shape themselves for a note that is wrong, and, when the note issues

from between the singer's lips, it is wrong--wrong from start to

finish, from mind to lips. Thus again is illustrated the intimate

connection between psychology and physiology in voice-production, and

the necessity of having every function concerned therein so thoroughly

trained that every act from mental concept to sounding voice is

correctly performed through a habit so thoroughly acquired that it has

become second nature. In common parlance one might say to the student

of song, "Get the correct voice-habit and keep it up," for that really

is what it amounts to, only it is necessary that great stress should

be laid on the word "correct."

It now becomes necessary to describe the larynx, and this I will

endeavor to accomplish without puzzling the reader with too many

technical terms. The study of the larynx was made possible by the

invention of the laryngoscope in 1855 by Manuel Garcia, a celebrated

singing-master. It is a simple apparatus--which, however, does not

detract from but rather adds to its value as an invention--and has been

a boon to the physician in locating and curing affections of the throat.

Its essentials are a small mirror fixed at an obtuse angle to a slender

handle. Introduced into the mouth it can be placed in such position

that the larynx is reflected in the mirror and thus can be observed

by the operator. Those who have had their throats examined with the

laryngoscope will recall that the operator wears a reflector over his

right eye. Through a central perforation in the reflector he views the

image, which is seen the more clearly for the light thrown upon the

laryngoscopal mirror by the reflector. It would be possible after

comparatively little practice with the apparatus for a singer to examine

his own larynx. But it would be most inadvisable for him to do so.

Either he soon would become "hipped" on the subject of innumerable

imaginary throat troubles, or his voice-production would become

mechanical, which is very different from the spontaneous adjustment

of the vocal tract described above.

N. B.--Vocal cords approximated]

1, Glottis. 2, True Cords. 3, False Cords. 4, Epiglottis. 5, Base of

Tongue. N. B.--Glottis open for inspiration]

1, Glottis. 2, True Cords. 3, False Cords. 4, Epiglottis. 5, Base of

Tongue. N. B.--Vocal cords approximated]

1, The Glottis (i. e., the opening between the opposed edges of the

Vocal Cords). 2, True Vocal Cords. 3, False Vocal Cords. 4, Epiglottis.

(N. B.--In singing, the "true cords" are closely approximated.)

V, Ventricles. T, Thyroid Cartilage. C, Cricoid Cartilage. W, Windpipe

or Trachea.

(N. B.--In STRAINING, the "false cords" are closely approximated.)]

The laryngoscope should not, in fact, leave the hands of the physician.

Invaluable for the detection of diseases of the throat which impair the

voice and which have to be cured either by treatment or operation before

the voice can be restored to its original potency or charm, its value

in studying the physiology of voice-production and the functions of

the vocal organs is doubtful. In fact, it is its use by amateur

laryngoscopists that has resulted in the promulgation of all kinds of

absurd theories of voice-study and in those innumerable pet methods of

vocal instruction, each one of which may safely be guaranteed to destroy

expeditiously whatever of voice originally existed. Fascinating as it

may seem to the singer to examine his own larynx while he is producing a

vocal tone--"during phonation," the physiologist would say--the value of

the deductions formed from such observation may be doubted, if for no

other reason than that the introduction of the mirror into the back of

the mouth makes the whole act of phonation strained and the effects

observed unnatural. In fact, as Mackenzie already has pointed out,

although the laryngoscope is invaluable in the recognition and treatment

of diseases which before only could be guessed at, "with the exception

of certain points relating to the 'falsetto' register, it can scarcely

be said to have thrown any new light on the mechanism of the voice." In

other words, the instrument belongs in the hands of the physician, not

in those of the singer.

The larynx, as I already have stated, is a small organ, on an average

two inches long and one and a half inch wide. The reader can form a good

idea of its location by the Adam's apple, which is its most forward

projection at the top.

From the singer's point of view the larynx exists for the sake of the

vocal cords--in order that they may be acted upon by certain muscles and

thus relaxed or tightened, lengthened or shortened, or by a combination

of these states properly adjusted to the note that is to be produced.

The vocal cords lie parallel to each other. The space between them

(the opening through which the air from the windpipe passes up into

the larynx) is called the glottis. With every loosening, tightening,

lengthening or shortening of the vocal cords or other effect of

muscular action upon them, the space between them--the glottis--alters

in size and shape. These subtle changes in the size and shape of the

glottis are, as I shall expect to show, of great importance in

voice-production. They form the first step in the actual creation

of voice.

The numerous and subtle adjustments and readjustments in shape of which

the larynx is capable could not be effected if its shell consisted of so

hard and unyielding a substance as bone. Consequently, it has to consist

of a substance which, while sufficiently solid to form a background for

the attachment of its numerous muscles, yet is sufficiently pliable to

yield with a certain degree of elasticity to the action of these. Nature

therefore has built up the larynx with cartilage, or gristle, providing

a framework made up of a series of cartilages, sufficiently joined to

form a firm shell surrounding the muscular tissue, yet, being hinged as

well as joined, capable of independent as well as of combined movement,

and, withal, possessing the requisite degree of pliability to respond in

whole or part to the extremely varied and often delicate action of the

laryngeal muscles--muscles which indeed are required to be as practised

and as sensitive to suggestion as if they were nerves.

The principal cartilage of the larynx is the thyroid or shield

cartilage, named from the Greek thureos (shield). It really consists

of two shields joined along the edges in front (its most forward upper

projection being the Adam's apple) and opening out at the back. The

thyroid is the uppermost cartilage of the larynx and the Adam's apple

is the uppermost portion of the front of the larynx. But as the shields

open out back of the Adam's apple, they slope upward and at the extreme

back each shield has a marked upward prolongation like a horn. By these

horns, enforced by membrane, the thyroid cartilage and through it the

whole larynx is attached to and is suspended from the hyoid bone, or

tongue-bone. This gives mobility to the larynx and freedom of movement

to the neck; and the larynx, while mobile as a whole, furthermore is

capable of an infinite number of muscular adjustments and readjustments

within itself.

At the back the lower edges of the thyroid rest upon the cricoid

cartilage, which derives its name from the Greek krikos, a

signet-ring. This is next in size to the thyroid. The broader portion,

the part which corresponds to the seal in a signet-ring, is at the

back. Attached at the back, the two cartilages do not, however, meet in

front. Place a finger on the Adam's apple, slide it down a little way,

and the slight depression there met with locates the front opening,

covered with yielding membrane, between the thyroid and cricoid


On the broader part of the cricoid--that is, on the part in the back of

the larynx--and rising inside the thyroid are two smaller cartilages,

the arytenoid or ladle cartilages, named from the Greek arutaina, a

ladle. Though smaller than either thyroid or cricoid, they are highly

important, because they form points of attachment for the vocal cords.

These (the vocal cords) are attached in front to the inner part of the

angle formed by the two wings of the thyroid just back of the Adam's

apple, and behind to a forward projecting spur at the base of each of

the arytenoid cartilages, which for this reason often are spoken of as

the "vocal process."

The vocal cords, as has been stated, lie parallel to each other, and

the space between them is known as the glottis or chink of the glottis.

Above the glottis and on opposite sides are two pockets or ventricles,

and above these are the so-called false cords or ventricular bands. The

pockets are, in fact, bordered below by the vocal cords and above by

the false cords. The false cords or ventricular bands (a name given to

them by Mackenzie) are the lower edges of membranous folds that form the

upper entrance to the larynx. Here are two pairs of small cartilages,

the cartilages of Santorini and the cartilages of Wrisberg. Usually

they are dismissed as of little or no importance. Yet they have, in

connection with muscles located in that part of the larynx, their roles

to play in those numerous adjustments and readjustments which, as I

shall show a little later on, are of the greatest importance in

voice-generation. For I consider, as I also will show, that the

numerous, indeed innumerable, and extremely subtle and exquisite

changes of shape of which the larynx is capable within itself, have

much to do with the actual creation of the tone which eventually issues

from the lips; although I believe this statement to be contrary to all

accepted authority. For the present, however, I must content myself

with this mere statement.

The larynx is protected above by a lid, a flexible, leaf-shaped

cartilage, the epiglottis. The gullet, or food-passage to the stomach,

is situated behind the larynx and windpipe, and the function of the

epiglottis is to close the larynx and to act as a bridge over which

food passes from the mouth into the gullet. But for the epiglottis, food

might get into the larynx and thence into the windpipe every time we

swallowed, with what distressing and even disastrous effect any one who

has ever "swallowed the wrong way" well knows. When open, on the other

hand, the epiglottis forms a beautifully smooth cartilaginous curve,

over which the sounding air, the tone, as it issues from the larynx,

is guided to the resonance cavities above the larynx, which are the

cavities of the mouth and of the nose. While parts of these cavities are

solid, like the roof of the mouth, other parts, like the soft palate,

are pliable; while the tongue is so astoundingly mobile that it

constantly can alter the resonance cavity of the mouth as to dimension

and shape.

The larynx is swathed and lined with membrane and muscle. These

membranes and muscles are named after the cartilages to which they are

attached, between which they lie, or which they operate. There is no

reason why they should be enumerated now. The function of the muscles

of the larynx is stated by all authorities with which I am familiar to

be twofold--to open and close the glottis (the space between the vocal

cords), and to regulate the tension of the vocal cords, because the

vibrations of these are considered the determining factor of vocal

pitch. Sir Morell Mackenzie, however, in describing the muscles of the

larynx in a passage couched in untechnical language, unconsciously gives

a hint of another purpose for which the complexity of muscles in the

larynx may exist. After speaking of the "innumerable little fingers of

the muscles which move the vocal cords," he continues: "These fingers

(which prosaic anatomists call fibres), besides being almost countless

in number, are arranged in so intricate a manner that every one who

dissects them finds out something new, which, it is needless to say, is

forthwith given to the world as an important discovery. It is probable

that no amount of macerating or teasing ever will bring us to 'finality'

in this matter; nor do I think it would profit us much as regards our

knowledge of the physiology of the voice if the last fibrilla of tiny

muscle were run to earth. The mind can form no clearer notions of the

infinitely little than of the infinitely great, and the microscopic

movements of these tiny strips of contractile tissue would be no more

real to us than the figures which express the rapidity of light and

the vast stretches of astronomical time and distance. Moreover, no two

persons have their laryngeal muscles arranged in precisely the same

manner--a circumstance which of itself goes a considerable way toward

explaining the almost infinite variety of human voices. The wonderful

diversity of expression in faces which structurally, as we may say,

are almost identical, is due to minute differences in the arrangement

of the little muscles which move the skin. The same thing holds good of

the larynx."

These are significant words. The distinguished physician who wrote them

might just as well have said that the generally prevailing theory that

in voice-production the muscles of the larynx exist solely to open and

close the glottis and to regulate the tension and hence the vibration of

the vocal cords, is incorrect. For they also exist in order to shape and

reshape the entire larynx within itself according to the note to be

produced, and the opening or closing of the glottis with the degree of

tension of the vocal cords resulting therefrom is but one detail in the

coordination of adjustments and readjustments which prepare the vocal

tract to produce the tone the singer hears in his mind. Nearly every

authority on the physiology of voice-production believes that the vocal

tone is produced solely by the vibration of the vocal cords, and that

the entire vocal tract situated above the vocal cords is concerned

merely with augmenting the tone and determining its timbre or quality.

Let us examine this theory and ascertain how tenable it is.

To begin with, the term "cord" as applied to the vocal cords is

misleading. It suggests a resemblance between the vocal cords and the

strings of a violin, which are capable of great tension, or at least

a resemblance between the vocal cords and the vibrating reed of a

reed-instrument. In point of fact, the vocal cords are neither strings

nor reeds, and are not even freely suspended from end to end or from one

end like reeds, but are attached along their entire lower portion to the

inner wall of the larynx. Therefore they are not cords, nor strings, nor

reeds in any sense whatsoever. They are shelves composed of flesh and

muscle, their substance resembles neither the catgut of which the

strings of stringed instruments are made nor the cane, wood or metal of

which the reeds of reed-instruments are formed; and the entire length of

each cord is a trifle more than half an inch in men and a little less

than half an inch in women. Almost every writer on voice appears to

consider the term "cord" as applied to them a misnomer. They have been

spoken of as membranous lips. "The vocal 'cord' is not a string, but

the free edge of a projecting fold of membrane," says Mackenzie. Yet it

is not only claimed but announced over and over again as a physiological

fact that the human voice, sometimes sweet and mellow, sometimes

tense and vibrant and with its great range, is produced solely by the

vibration of two projecting folds of membrane, free only at their edges

and at their longest only a little over half an inch in length.

At least one writer on voice-production, Prof. Wesley Mills, appears to

have doubted the correctness of the old and oft-repeated theory.

"Allusion must be made," he writes in "Voice-Production in Singing and

Speaking," "to the danger of those engaged in mathematical and physical

investigation applying their conclusions in too rigid a manner to the

animal body. It was held until recently that the pitch of a vocal tone

was determined solely by the number of vibrations of the vocal bands,

as if they acted like the strings of a violin or the reed of a clarinet,

while the resonance chambers were thought to simply take up these

vibrations and determine nothing but the quality of tone.... It seems

probable that the vocal bands so beat the air within the resonance

chambers as to determine the rate of vibration of the air of these

cavities, and so the pitch of the tone produced." This at least shows

dissatisfaction with the old theory and attaches some share of their

due importance to the resonance cavities, but it still is far from

describing the correct phenomenon of voice-production.

Show a lateral section of a larynx to a trumpet or horn player and he

will at once recognize its similarity to the cupped mouthpiece and tube

of trumpet or horn, the cup in the larynx being formed by the ventricles

or pockets above the vocal cords. Extend the picture so that it includes

not only the larynx but the resonance cavities of the head as well, and

the cornet, trumpet or horn player will recognize the similarity to the

tube of his instrument as it turns upon itself. The manner in which the

lips shape themselves as the player blows into the instrument, the form

and size of the cup, the gyration and friction of the air within it and

within the bent portion of the tube, determine the pitch and the quality

of the tone that issues from the bell of the instrument.

The shape assumed by the lips, which are capable of many exquisite

variations in shape, conditions the form of the air-column as it enters

the cup of the trumpet or horn. This I believe to be one important

function performed for the larynx by the vocal cords, which Mackenzie,

with an aptness he could not have appreciated, called the lips of the

glottis. They are, in fact, the lips of the essential organ of voice,

the larynx. If they are looked at from below they will be seen to be

bevelled, and their resemblance to lips even more striking.

While, however, the importance of the vocal cords in tone-production

has been overestimated, I should be going to the opposite extreme if I

limited their importance to their function as the lips of the glottis.

Not only are they lips, but vibrating lips, their vibrations, however,

requiring enforcement through the sympathetic vibrations which they

generate within the cup of the larynx and in the cavities above. As

lips, the vocal cords shape the air-column as it enters the larynx, to

the required note; as vibrating lips--set into vibration by the very

air-column to which they have given shape--they start the vibrations

essential to pitch and pass them along into the cup of the larynx, which

also has shaped itself to the note and where gyration and friction begin

to reinforce the vibrations started by the cords. What is true of the

cup also is true of the resonance-cavities. In other words, the entire

vocal tract, from cords to lips, shapes and reshapes itself with

reference to the tone that is to be produced, and what thus goes on

above the vibrating cords cooperates to produce the effect formerly

attributed to the cords alone.

The fact that the cup of the larynx subtly changes its shape for each

tone produced, makes the hitherto obscure subject of registers of the

voice, which many writers have written around but none about,

perfectly clear. The cup assumes what may be called a generic shape for

each register, and then goes through subtle adjustments of shape for the

different notes within each register. But this is a subject to be taken

up in detail later.

The reader now will understand why at different points in this chapter

I have emphasized the fact that the larynx as a whole and throughout all

its parts is capable of numerous adjustments in shape, and that the same

is true of the resonance-cavities. The vocal tract of an accomplished

singer is capable of as many adjustments as a sensitive face is of

changes in expression. This phenomenon is the vocal tract making ready

to generate, vitalize and emit the tone suggested by the mind--mind

pressing the button, the physical organs of voice-production doing

the rest.