Singing & The Human Voice

Times change - superficially - but singers, orators, story-tellers, actors have always occupied a special place in society - a focal point - a mouthpiece - a reflection, a distillation by a few, of the inner-lives and feelings of the many.

Generally respected, often idolized - sometimes seen as politically threatening, sometimes as entertainment - seeming to fulfill a need - giving sections of society a single voice - an expressive valve to release pressure - possessing skills, techniques and talents which we classify as part of  The Arts - but a part that has in common - the use of the human voice.

This essay wishes to concentrate on singers and singing.

Times change.

Not too long ago (about 150 years ago - according to this article) - something very strange to our contemporary understanding - performances of singing and music in general were entirely live - the art was only connected to the immediate humanity of the performers and audience.

"For more than a hundred years, the history books have noted that Thomas Edison’s words, “Mary had a little lamb,” inscribed on tin foil and played back, were the first recordings of a human voice into a visible medium. But in fact, a French inventor and tinkerer named Edouard-Leon Scott de Martinville achieved such a recording 17 year earlier, on April 8, 1860, using a device he had patented three years prior.
Leon Scott’s device, which was called the phonoautograph, had a barrel-shaped horn attached to a stylus made of a boar’s tail hair. The stylus etched sound waves onto sheets of paper blackened by smoke from an oil lamp. A later version (shown at right) used lamp-blackened paper on a drum or cylinder. Another version drew a line on a roll of paper.
Unfortunately for Leon Scott, his invention allowed only for recording – not for playback.
So it wasn’t until 2008 that researchers at Lawrence Berkeley National Laboratory in Berkeley, Calif., were able to convert his etchings to a digital format. Using a virtual stylus created by computers, the digitized etching was converted to sound by lead researcher and audio historian David Giovannoni and his team at Creative Sounds. The recording is now licensed by First Sounds."
Courtesy siliconcowboy.

Of course today we have wall-to-wall music, while shopping, sometimes in the background while we listen to news headlines, travelling in a lift, sitting in a pub.
Music is seen very much as a commodity, commercial pressures artificially increase our exposure to it and inflate the importance of performers & recording artists - elements which are partly responsible for changing our perception - clouding our understanding & leading it, perhaps, far away from the mysteries and wonders involved in & represented by singing itself - when examined simply, in isolation from all these influences.

That is what I hope to do in this essay - look closely at the physiology of singing.

Where better to start than with the instrument itself.


We all possess an instrument (apart from very rare exceptions).

"Those who are physically mute may have problems with the parts of the human body required for human speech (the throatvocal cordslungsmouth, or tongue, etc.). Being mute is often associated with deafness as people who have been unable to hear from birth may not be able to articulate words correctly (see Deaf-mute). A person can be born mute, or become mute later in life as a result of injury or disease.
Trauma or injury to the Broca's Area of the brain can cause muteness."

Courtesy Wikipedia 

Fascinating in its versatility, its ability to mimic, to express with combined melody and lyric - a vast range of imagination and emotion.
"The human voice consists of sound made by a human being using the vocal folds for talkingsinginglaughingcrying,screaming, etc. Its frequency ranges from about 60 to 7000 Hz. The human voice is specifically that part of human sound production in which the vocal folds (vocal cords) are the primary sound source. Generally speaking, the mechanism for generating the human voice can be subdivided into three parts; the lungs, the vocal folds within the larynx, and the articulators. The lung (the pump) must produce adequate airflow and air pressure to vibrate vocal folds (this air pressure is the fuel of the voice). The vocal folds (vocal cords) are a vibrating valve that chops up the airflow from the lungs into audible pulses that form the laryngeal sound source. The muscles of the larynx adjust the length and tension of the vocal folds to ‘fine tune’ pitch and tone. The articulators (the parts of the vocal tract above the larynx consisting of tonguepalatecheek,lips, etc.) articulate and filter the sound emanating from the larynx and to some degree can interact with the laryngeal airflow to strengthen it or weaken it as a sound source.
The vocal folds, in combination with the articulators, are capable of producing highly intricate arrays of sound.The tone of voice may be modulated to suggest emotions such as angersurprise, or happiness.Singers use the human voice as an instrument for creating music.

Voice types and the folds (cords) themselves

A labeled anatomical diagram of the vocal folds or cords.
Adult men and women have different sizes of vocal fold; reflecting the male-female differences in larynx size. Adult male voices are usually lower-pitched and have larger folds. The male vocal folds (which would be measured vertically in the opposite diagram), are between 17 mm and 25 mm in length. The female vocal folds are between 12.5 mm and 17.5 mm in length.
As seen in the illustration, the folds are located just above the vertebrate trachea (the windpipe, which travels from the lungs). Food and drink do not pass through the cords but instead pass through the esophagus, an unlinked tube. Both tubes are separated by the epiglottis, a "flap" that covers the opening of the trachea while swallowing.
The folds in both sexes are within the larynx. They are attached at the back (side nearest the spinal cord) to the arytenoids cartilages, and at the front (side under the chin) to the thyroid cartilage. They have no outer edge as they blend into the side of the breathing tube (the illustration is out of date and does not show this well) while their inner edges or "margins" are free to vibrate (the hole). They have a three layer construction of an epithelium, vocal ligament, then muscle (vocalis muscle), which can shorten and bulge the folds. They are flat triangular bands and are pearly white in color. Above both sides of the vocal cord is the vestibular fold or false vocal cord, which has a small sac between its two folds (not illustrated).
The difference in vocal folds size between men and women means that they have differently pitched voices. Additionally, genetics also causes variances amongst the same sex, with men and women's singing voices being categorized into types. For example, among men, there are bassbaritonetenor and countertenor (ranging from E2 to even F6), and among women, contraltomezzo-soprano and soprano (ranging from F3 to C6). There are additional categories for operatic voices, see voice type. This is not the only source of difference between male and female voice. Men, generally speaking, have a larger vocal tract, which essentially gives the resultant voice a lower-sounding timbre. This is mostly independent of the vocal folds themselves.

Physiology and vocal timbre

The sound of each individual's voice is entirely unique not only because of the actual shape and size of an individual's vocal cords but also due to the size and shape of the rest of that person's body, especially the vocal tract, and the manner in which the speech sounds are habitually formed and articulated. (It is this latter aspect of the sound of the voice that can be mimicked by skilled performers.) Humans have vocal folds that can loosen, tighten, or change their thickness, and over which breath can be transferred at varying pressures. The shape of chest and neck, the position of the tongue, and the tightness of otherwise unrelated muscles can be altered. Any one of these actions results in a change in pitch, volume, timbre, or tone of the sound produced. Sound also resonates within different parts of the body, and an individual's size and bone structure can affect somewhat the sound produced by an individual.
Singers can also learn to project sound in certain ways so that it resonates better within their vocal tract. This is known as vocal resonation. Another major influence on vocal sound and production is the function of the larynx, which people can manipulate in different ways to produce different sounds. These different kinds of laryngeal function are described as different kinds of vocal registers. The primary method for singers to accomplish this is through the use of the Singer's Formant, which has been shown to be a resonance added to the normal resonances of the vocal tract above the frequency range of most instruments and so enables the singer's voice to carry better over musical accompaniment.

Vocal registration

Vocal registration refers to the system of vocal registers within the human voice. A register in the human voice is a particular series of tones, produced in the same vibratory pattern of the vocal folds, and possessing the same quality. Registers originate in laryngeal functioning. They occur because the vocal folds are capable of producing several different vibratory patterns. Each of these vibratory patterns appears within a particular Vocal range  of pitches and produces certain characteristic sounds. The term register can be somewhat confusing as it encompasses several aspects of the human voice. The term register can be used to refer to any of the following:
  • A particular part of the vocal range such as the upper, middle, or lower registers.
  • resonance area such as chest voice or head voice.
  • phonatory process.
  • A certain vocal timbre.
  • A region of the voice that is defined or delimited by vocal breaks.
  • A subset of a language used for a particular purpose or in a particular social setting.
In linguistics, a register language is a language that combines tone and vowel phonation into a single phonological system.
Within speech pathology the term vocal register has three constituent elements: a certain vibratory pattern of the vocal folds, a certain series of pitches, and a certain type of sound. Speech pathologists identify four vocal registers based on the physiology of laryngeal function: the vocal fry register, the modal register, and the falsetto register, and the whistle register. This view is also adopted by many vocal pedagogists.

Vocal resonation

Vocal resonation is the process by which the basic product of phonation is enhanced in timbre and/or intensity by the air-filled cavities through which it passes on its way to the outside air. Various terms related to the resonation process include amplification, enrichment, enlargement, improvement, intensification, and prolongation; although in strictly scientific usage acoustic authorities would question most of them. The main point to be drawn from these terms by a singer or speaker is that the end result of resonation is, or should be, to make a better sound.There are seven areas that may be listed as possible vocal resonators. In sequence from the lowest within the body to the highest, these areas are the chest, the tracheal tree, the larynx itself, the pharynx, the oral cavity, the nasal cavity, and the sinuses."

Thoracic diaphragm

In the anatomy of mammals, the thoracic diaphragm (E) - or simply the diaphragm 
(Ancient Greek:διάφραγμα diáphragma "partition"), is a sheet of internal skeletal muscle that extends across 
the bottom of the rib cage. The diaphragm separates the thoracic cavity (heart, lungs & ribs) from the 
abdominal cavity and performs an important function in respiration: as the diaphragm contracts, the volume 
of the thoracic cavity increases and air is drawn into the lungs.

A "diaphragm" in anatomy can refer to other flat structures such as the urogenital diaphragm or pelvic 
diaphragm,but "the diaphragm" generally refers to the thoracic diaphragm. 
Other vertebrates such as amphibians and reptiles have diaphragms or diaphragm-like structures, 
but important details of the anatomy vary, such as the position of lungs in the abdominal cavity.


The diaphragm functions in breathing.

During inhalation, the diaphragm contracts, thus enlarging the volume of the thoracic cavity (the external
intercostal muscles also participate in this enlargement). This reduces intra-thoracic pressure:

In other words, enlarging the cavity creates suction that draws air into the lung, or lungs.

Cavity expansion happens in two extremes, along with intermediary forms.

When the lower ribs are stabilized and the central tendon of the diaphragm is mobile, a contraction brings
the insertion (central tendon) towards the origins and pushes the lower cavity towards the pelvis, allowing the
thoracic cavity to expand downward.

This is often called belly breathing. When the central tendon is stabilized and the lower ribs are mobile,
a contraction lifts the origins (ribs) up towards the insertion (central tendon) which works in conjunction with
other muscles to allow the ribs to slide and the thoracic cavity to expand laterally and upwards.

When the diaphragm relaxes, air is exhaled by elastic recoil of the lung and the tissues lining the thoracic cavity.

Assisting this function with muscular effort (called forced exhalation) involves the internal intercostal muscles
used in conjunction with the abdominal muscles, which act as an antagonist paired with the diaphragm's

The diaphragm is also involved in non-respiratory functions, helping to expel vomit, feces, and urine from the
body by increasing intra-abdominal pressure, and preventing acid reflux by exerting pressure on the
esophagus as it passes through the esophageal hiatus.
In some non-human animals, the diaphragm is not crucial for breathing; a cow, for instance, can survive fairly
asymptomatically with diaphragmatic paralysis as long as no massive aerobic metabolic demands are made of it.

Courtesy Wikipedia Human Voice & Thoracic Diaphragm.

A few critical phrases from the above quotes:

"this air pressure is the fuel of the voice"

"The main point to be drawn from these terms by a singer or speaker is that the end result of 
resonation is, or should be, to make a better sound."

"Assisting this function with muscular effort (called forced exhalation) involves the internal 
intercostal muscles used in conjunction with the abdominal muscles . . ."

Remember, all the time we are referring to sound with regard to singing - we consider that the medium of 
transmission is air.

It is quite remarkable how sensitive this medium is for the transmission of sound.

Here is a thought experiment.

Imagine yourself in a fairly large hall - the hall is perfectly quiet.
Another person at an opposite end of the hall utters a soft sound - such as "Pssst".

Not only will you very probably be able to hear that sound quite adequately, but you can also imagine 
that were you positioned anywhere else in that space, any of the corners for instance - including the top corners
- you would be able to hear that sound equally well.

What this means is that the small sound is transmitting itself, through the air - to every area of that space - 
simultaneously - it is therefore effecting every molecule of air in that space.

Unlike any other musical instrument, the processes of the human voice are invisible - it all happens "inside" - 
and importantly there are no mechanical, visible references for the pitching of sound.

Here are two scientific terms referring to important aspects of sound.

Frequency & Amplitude.

Frequency is responsible for the "pitch" element in all sound - and describes the number of complete cycles 
of vibration in a given amount of time - in singing this refers to the movement of the vocal folds.
Moving at astonishing speeds - for example - to sing the note "A" above middle "C" - requires the vocal folds 
to vibrate at a frequency of 440 Hz - that is 440 complete cycles of movement per second - the "A" an octave 
above that would require a frequency of 880 Hz.

Amplitude is responsible for the "loudness" element in sound - and essentially describes the excursion of the 
vibrating body - how far it travels in each cycle of frequency - thus communicating "frequency information" to 
more or fewer air molecules

How do we learn to effect the frequency or pitch of the sound we produce?

It's quite a mystery really - and has its invisible roots in our ability to mimic, and learn how to respond with 
mimicry as part of communication - part of our language learning skills - skills which are innately engaged 
in our infancy, but which we adapt constantly throughout our lives - subliminally, naturally and unconsciously.

A skill that most of us take completely for granted - but which also reveals a host of intricate & complex 
physiological tricks that we have learned and mastered.

One of them being our ability to control the output of our voices by imagination alone - we hear inside our minds
the sound we wish to produce, and usually, out it comes - the pitch element being just a fraction of the control we 
have learned - but this skill is obviously of paramount importance to a singer.

In the voice there are no keys, no valves, no frets to visually assist pitch accuracy - it is all done with the 

imagination & the will.

It is slightly less of a mystery how we learn about amplitude - if we wish to ensure that we are heard - we learn
how to shout - if we wish to impart a secret - we whisper.

In shouting - we energetically supply more air to our message - encouraging the vocal folds to make larger 
excursions - they in turn, assist us in being heard by raising the pitch slightly from our normal speech frequency 
range - aspects of registration.

In whispering we do not engage the vocal folds at all - we simply use resonance and articulation to modulate 
the air of our breath - aspects of resonation.

These two areas of registration and resonation lead to expose a common but understandably subtle
mis-conception regarding a singer's practice.

To the novice or the un-initiated - singing appears to be oriented in association with the mouth.
After all, that is the activity we see, that is where the words are formed - that is where the sound escapes - that
is where we imagine that we hear the sound coming from.

All too often though, effort and focus is wasted in this area, in catastrophic neglect of the root of the sound
which is at the vocal folds themselves - hidden - doing all of their work - invisibly.

The vocal folds can only do their work when there is a suitable and adequate air supply.

It is the nature & control quality of this air supply which has the largest influence on virtually all aspects of singing.

If this relationship between breathing, the role of the diaphragm, the dependence of the vocal folds on the quality
of air supply - and the physiological support of one's singing efforts - is misunderstood, or not personally explored -
it becomes difficult for an individual singer to find areas in which to make dramatic and lasting improvement.

All other considerations in singing are of secondary importance to practically incorporating the understanding of
this fundamentally critical aspect.

What does this mean for the singer, in practical terms?

It provides a key to improvement - allowing the focus of effort to shift from an over-reliance on elocution - using
syllables and consonant components as "foot-holds" in which to erroneously place effort.
It allows a singer to strip away all secondary measures for success, which will naturally benefit from a focus on
this area of prime importance.

Vowel components and Consonant components.

Without exception, all consonant components of singing - either fully or partially impede or transfer the flow
of air - the air proceeding from the vocal folds.

Without exception, all vowel components of singing - permit and encourage the free flow of air - the air proceeding
from the vocal folds.

It is clear then, that on the journey that the air travels, by the time vowels or consonants are formed to modulate
the sound - the vocal folds have already supplied their contribution.

It is in the control of this contribution that fundamental improvements may be made - affecting all other areas -
affecting psychologically, a singer's confidence & ability to relax, affecting physically the amount of false effort and strain
introduced - it will demonstrably have positive effects on an even tone production and on the perceived tone itself -
it will offer opportunities to improve dynamic range & control.

Recommended method for practice.

To this end, I recommend the following method of practice - to expose and gain confidence in the root of the sound.

Separate the vowel components of the song you are working on - ensuring that you identify them correctly as the
actual sounds produced when incorporated into the words.
There are many more than the traditional grammar of A  E I O & U - and many of the vowel components are

"A diphthong - Greekδίφθογγοςdiphthongos, literally "two sounds" or "two tones"), also known as a gliding vowel
refers to two adjacent vowel sounds occurring within the same syllable
Technically, a diphthong is a vowel with two different targets: That is, the tongue moves during the pronunciation of 
the vowel. In most dialects of English, the words eyehayboy,low, and cow contain diphthongs.
Diphthongs contrast with monophthongs, where the tongue doesn't move and only one vowel sound is heard in a 
syllable. Where two adjacent vowel sounds occur in different syllables—for example, in the English word 
re-elect—the result is described as hiatus, not as a diphthong."

Courtesy Wikipedia Diphthong.

bviously, this technique will be more easily applied to a ballad type song than a rapid-fire tongue-twister - 
but practice benefits are transferable.
Sing through the song - devoid of consonants - creating a smooth, perfectly legato "tube" of sound that seamlessly
changes from one vowel sound to another - paying attention to dipthongs with regard to the particular component
which is dwelt on in preference - and the different posturing of the throat and mouth necessary to enable distinction and purity 
of each vowel sound.

You will find that all of the effort & control is now being supplied by your diaphragm - you will find that you need a 
lot more air than you thought necessary - for all of those minute and temporary impediments to the air flow (the consonants)
are no longer there to help you conserve breath.

What you will find also is what is referred to above as "forced exhalation" - the diaphragm in conjunction with the stomach muscles
- allowing you to control the air flow.
Notice the difference between this and a natural exhalation, which is simply the relaxation of the diaphragm.
Notice also that the requirements of singing necessitate "forced inhalation" as well - sometimes taking a full breath 
in the shortest possible time.
Both are important.

Notice also that it is difficult to transform a natural inhalation or exhalation into a forced (assisted) one - once it has
 already commenced.

Breathing exercise.
Practice a deep in-breath in as short a time as possible - followed by what I call "the lock" - hold the stomach muscles in the position of the 
full breath - and then proceed with an assisted exhalation - being very conscious of how you are rationing the air flow,
you are now in control - by increasing the pressure of the stomach muscles during exhalation - you are delivering more air
to the area of the vocal folds - what you will do when you wish to sing louder.
Be conscious of the evenness with which you control this exhalation - that will assist in the production of a steady,
even tone.

So after practicing the chosen & suitable song in this manner - devoid of consonants - and each phrase between breaths
is one long tube of sound - no breaks in the sound at all - every note within each phrase is glided to and from - and the vowels 
are seamlessly changing from one clear, well defined vowel sound to another - you will hopefully notice wonderful 
improvements in your ability to confidently rise and fall with the contour of the melody - because you have been paying attention 
to the key area of support in your singing.

Now comes the time to re-apply the consonants.
We can give them some special treatment as well - & care must be taken.
We have already discovered that consonants involve restricting or shifting the air-flow - explore for yourselves.
Either the lips, the tongue, the teeth and lips or the glottis - or some combination of those - temporarily stop the air flow.
and the harder consonants especially - "T" "D" "P" "F" etc. rely on the small explosive release of the air flow to sound.
Others are slightly gentler in action and allow the air flow to continue, but re-channel the air through the nasal passages
- consonants such as "R" "M" or "N".

However all of this activity can be unsettling for the vocal folds - so care should be taken to incorporate the flow of air from the
consonant components into the air flow already in motion from vowel production - keeping it all moving forwards.
To realise that consonants also rely on air movement for audibility is a clue as to how to make them more clearly defined
Clumps of consonants should be gently teased apart - allowing each separate component to sound - for example in the word "tree"
there is a clump at the beginning of "T" & "R".
Imagine as far as possible that these consonant components wrap themselves around the long tube of sound already worked on
in the first part of this method - enclosing it rather than chopping it up.

Of course, singing is exceptional because it also carries the component of linguistic meaning - it tells a story.
As well as employing the subtle and directly emotional language of melody - singing can clarify and focus the emotional content
with its use of words - our everyday language.

However when most singers learn songs and perform the subject matter of the song, it is at most, remotely personal to themselves.
This brings us to characterization - bringing a song to life - making it your very own.

The process is the reverse of when we normally recount a story from our everyday lives - where we have in place the memories, 
the pictures, the emotions we can recall feeling - and automatically we engage all of these in our recollection.

When reciting a song - we need to find all of these factors - we need to understand the logic of the words, from the point of view
of the character singing them.
We need to have as clear a picture as possible - in place in our minds - of the circumstances resulting in the song.
Again - it is a task for the imagination - to help make the song our very own - and to make it convincing in performance.