- Hi, my name is Doctor Dan
and today I'm going to be showing you
live footage of a singer's vocal folds
and then we're going to learn how the singing voice works.
I've got heaps of great video footage
and animation to show you, so let's get started.
[Female Performer] Sound check.
Check one, check two.
(mellow rock music)
(crowd cheering)
(mellow music)
Have you ever wondered how the human voice works?
We've all got one,
but because it's located inside your neck
it's difficult to get to, making it virtually impossible
to directly see and feel.
Laryngologist examine the larynx,
what some people call the voice box,
using a technique called endoscopic examination.
They do this with either a fixed scope,
which is inserted into the mouth,
or a flexible scope that is passed through the nasal cavity.
The scope has a small light and camera that illuminates
and videos the internal workings of the larynx.
Here we can see the vocal folds,
with the bottom of the screen
showing the front of the singer
and the top of the screen
displaying the arytenoids,
which bring the vocal folds together for speech and singing.
The video we are looking at here is of an adult sized voice.
Interestingly, there is a difference in the size of
the larynx between men and women.
With the male adult voice being larger
than the female adult voice.
And as you might suspect, the adult voice is
significantly bigger than the pre-pubescent voice.
Baby bear, mama bear, and papa bear
is a good way to remember it.
And this is the reason why the superior thyroid notch,
what most people call the Adam's apple,
protrudes on most adult men
and why it doesn't protrude on most adult women.
The size difference also explains, in part,
the various voice types soprano, alto, tenor and bass,
but more about that in a moment.
When singing teachers and vocal coaches
work with a certain student's voice,
they often approach it as one whole system
that is made up of four components.
The actuator, the vibrator,
the resonator
and the articulators.
When explaining these four components,
Chalmers writes, the actuator is the breath,
the power source, and energy of the voice.
The vibrator is the pair of vocal folds,
which is valve like structure of muscle and tissue.
The resonator is the vocal tract.
A combination of the larynx, the pharynx
and the oral cavity amplifying the sound.
And finally, the articulators are primarily the tongue
and lips which shape the sound into meaningful units.
Every engine needs fuel and your voice is no different.
Your breath, or your actuator, fuels your voice.
Breathing is split into two phases,
inhalation and exhalation.
To inhale the diaphragm contracts,
drawing air into the vocal tract through the larynx
and down into the lungs.
For the singer, the exhalation phase is managed primarily by
the abdominals and the obliques.
Learning to manage the outflow of air,
as well as adjusting the sub glottal pressures
in accordance with the song genre, is just part of
the challenge facing the developing singer.
As the breath stream passes through the larynx,
it flows between two muscular bodies, known as
vocal folds, historically referred to as vocal cords.
The structures of each fold has five layers.
Number one, the outer layer, known as the epithelium.
The superficial layer of the lamina propria,
or Reinke's space is number two.
Number three, the intermediate layer of the lamina propria,
which is made up of elastic fibers.
Number four, the deep layer of the lamina propria,
which contains collagenous fibers
and finally, the main body of the vocal fold,
the vocalis muscle, the middle of
the thyroarytenoid muscle.
When you were born, your vocal folds were approximately
three millimeters in length and as we age into adulthood,
they grow to between nine to 13 millimeters for women
and 15 to 20 millimeters for men.
To create sound, the vocal folds
are drawn together momentarily, closing the glottis.
Glottis is the term given to the space
directly between the vocal folds.
The air pressure builds beneath the closed vocal folds
and the glottis starts to open from the underside through to
the top side, allowing air to escape between
the leading edges of the vocal folds.
When singing in A4, the same tuning pitches in orchestra,
this single close, open, close motion of the glottis
is repeated 440 times per second.
Measured in hertz,
the oscillatory rate of the vocal folds, in part, gives us
an insight into the voice type of the singer.
Here we see the approximate oscillatory rates
of the different voice types.
Notice the difference between the lowest approximate note
of the bass voice classification as C2 when compared to
the highest oscillatory value of the soprano's E6.
65 hertz through to 1318 hertz.
I'm pointing out the obvious when I say, the higher you sing
the faster the vocal folds have to move.
The sound formed by the oscillating vocal folds
and carried on the breath stream, is raw
and requires quite a bit of post production.
The resonator, often referred to as the vocal tract,
is measured from the glottis through to the outer edge
of the lips and nostrils.
As sound travels from its point of origin,
the vocal folds,
it resonates within and along the flexible spaces of
the larynx, pharynx,
oral and nasal cavities.
The sound that emanates from the lips and nostrils,
is transformed from a rudimentary buzz to a full
and resonant acoustic that has been shaped and molded by
the ever changing space of the vocal tract.
It's the ability of the skilled singer to consistently
and accurately change the vocal track shapes according to
the song being sung, that conveys the emotional value
of the lyric via a variety of tonal colors.
But it's not only the resonance of the sound that is shaped.
Human beings can fashion the sound into understandable
language with the use of the articulators.
The tongue, the lips, the hard and soft pallet,
as well as the jaw to some extent, combine to form
the building blocks of language, vowels and consonants.
It was once thought that the voice was
a simple linear system with
sound only ever flowing up and out.
Now, we understand that the voice is in fact
a non linear system
with each of the four components
interacting with one another.
So, for example a high level of breath pressure
being supplied by the actuator through the larynx,
can influence the oscillatory patterns of the vibrator,
causing the vocal folds to come together
with higher levels of force.
This in turn releases air through the glottis
at a slower rate, which only serves to
increase the air pressure even further.
It is the multiplicity of these interactions
between the four components that make the human voice
one of, if not the most complex instruments to
learn to use and sing with.
Every developing singer aims
to coordinate the four components of the voice,
so that each plays its role in perfect synergy with
the other three components.
Of course, there is much more to singing than
the mechanics of the voice, (mellow music)
but we'll leave that explanation for another day
and another video.
And if you're looking for more learn to sing videos
then I invite you to check out my channel
Dr Dan's Voice Essentials
and subscribe for weekly learn to sing instruction.
I look forward to seeing you again soon.
I'm Doctor Dan, sing well