The dimensions of the thyroid cartilage change the pitch

I got this question from an elite voice adviser.
“Regarding the figure of the thyroid cartilage shape when producing fluctuating pitches: Is it true that it is easy to let out a low-pitched voice when the shape is narrowed and if it’s widened it is easy to let out a high-pitched voice? Also, what is the reason behind this?”
I’ll explain and answer below.
If you see the thyroid cartilage from the top, it almost looks triangular.
Please refer to the figure below.


The a’& a are top, b&b’ and c&c’ are bottom of triangle. The left figures shows the shape of the thyroid cartilage when narrowed, and the right figure shows the thyroid cartilage when the shape is widened.
a&a’ are projections of the pharynx viewed from the front side, b,d,c&b’,d’,c’ are the back side, b&b’ are the left side and c&c’ are the right side.
The vocal cord line is a or a’ through d or d’.
When comparing the two triangles, a from d has a longer line length than a’ from d’. This means that the right vocal cord is shorter than the left one.
The elongated vocal cord is in connection to the reason behind how the voice pitch fluctuates, assisting in producing a low-pitched voice and the shorter vocal cord assists in producing the high-pitched voice.
These are the source mechanics of pitch production. When comparing these mechanics to the strings of a musical instrument, the same is true. Longer/thicker strings make a low pitched sound and shorter strings make a higher pitched sound.
However, you have to consider the size of the vocal cord as well. It displays a degree of thickness but not exactly like instrumental strings.
To answer the vocal advisor’s question, the statement is true. The figure of the thyroid cartilage shape, when narrowed does indeed make it easier to let out a low-pitched voice, meanwhile, when it is widened, it is easier to let out a high-pitched voice.
The male thyroid cartilage is generally larger and narrow in shape, whereas the female thyroid cartilage shape is smaller and wide. The left one looks like male thyroid cartilage and the right one looks female, in the above figure.
Please take into consideration, that each person does have individuality and the measurements do vary.
What kind of a thyroid cartilage do you have?



Make the impression of your voice within the first 3 seconds

First impressions are often made quickly. Regarding ‘the voice,’ the first impression is usually decided by the audience or listener after only the first 6 seconds, according to some surveys.
Challenging the accuracy of the previous statement, I opted to run my own study to test how long the voice is heard before the first impression is decided.
First, I recorded, “Good morning everyone. The weather today is cloudy with occasional showers. Although, you can expect warm temperatures later this afternoon…..” I read the sentences slowly without frequent pauses as much as possible. Then, I read the same sentences again. Secondly with a clear voice and finally with a thick voice.
I then played the recording to a target audience.
Before starting the test, I asked them, “Please tell me the exact moment in time (to the second) when your first impression was decided after hearing the voices.”
As a result, the average time was approximately 3 seconds.
Of course, they accurately judged the delivery and overall impression also, categorizing the voices as: Good voice, Reliable voice, Terrible voice, or Weird voice.
However, some of the results did have subjective judgment, and were vague in details when targeted for comparison.
Therefore, I think that 3 seconds is not the absolute value of the total impression as a whole. Although it is certain that the vocal impression was made faster than the impression of appearance.
In the case of appearance, the subjects decided the overall total impression after observing the face, attitude and factoring in subjective personal preference.
This study concludes that people make the impression after thinking.
However, in the case of voice, people make an intuitive almost immediate decision about the initial impression.
When I attended at audition for a record company I observed that the judges, judged soon after the song was sang. This is a very fair approach. Similar to when a person previews a CD for purchase. Usually not every song on the album is good. A lot of the time we purchase it anyway, using fair judgment, factoring the quality of the album as a whole, not just one song.
Vocal impressions are steadfast, so be mindful next time you make a vocal impression.


Note:In the case of singing, the impression is decided by the first one phrase. The impression of singing usually only has two initial impressions, ‘good at singing’ or ‘bad at singing.’
Furthermore, once people make a decision regarding a first impression, it cannot be changed easily.
We tend to decide that a person is a good singer if they are good at the starting point. Hence, if they are off to a bad start we tend to label them as a bad singer.

Trade off about lifting the corners of the mouth.

This topic is very important.
Maybe, you’ve heard that vocal coaches often say, “Lift the corners of the mouth. Sing like you are smiling!”
I’ll explain some positive and negative points about lifting the corners of the mouth, when singing.
Good point:
When you lift or extend the corners of the mouth, the space of oral cavity and pharyngeal cavity enlarge to maximum capacity.
The space is really important to make harmonic sounds or echoes, just like a music instrumental. Therefore, this stretching causes the voice to increase the potential to make the voice better.
Bad point:
When you lift the corners of the mouth, the orbicularis oris muscle is stretched and the front teeth either stick to the lips, or the front teeth are bare. When the orbicularis oris muscle does not move it obstructs the movement of the lips, which tunes the voice, and becomes harder to produce good sound.
Please use the way that is the most comfortable and suitable for you, after you understand what the exact trade off is.


The position of the pharyngeal cavity

The human throat can be compared and contrasted to an acoustic guitar.


The important part is the components that are relevant to sound production, which are:

If the guitar is compared to the vocal organs:
1:Head=the cricothyroid muscle
2:Strings=the vocal cord
3:Body= the resonance chamber.

The body of the guitar is the most relevant to “making sound.” The material components and the structural composition decide the strength and quality of that sound.
‘The Book of Singing,’ states that, “the vocal cord is important but the resonance chamber is the most vital.”
The pharyngeal cavity’s role of sound production relies on the resonance chamber, the positioning, the ease of mobility and the space available.
The pharyngeal cavity is located behind the hyoid bone.
The following picture shows the hyoid bone(yellow) and the pharyngeal cavity(red) captured by a CT scan.


If the hyoid bone moves forward, the epiglottis is going to be able to stand vertically very easily. Which assists in making the space of the pharyngeal cavity maximally open, which is commonly referred to as, “opening the throat.”
You cannot expel or produce a good voice unless the hyoid bone is easily moved. Moving it smooth and easily will in turn create less stress to the area.
You should always refrain from opening your throat forcibly. Furthermore, the wrong way when opening your throat is pulling down your tongue quickly and with too much strength. The parts of the oral cavity and pharyngeal cavity can become enlarged with this way, and will harden the tongue and muscles around larynx. When this hardening occurs you will lose flexibility of the tongue and muscles around larynx, which I do not recommend.
I would like you to achieve and produce a high quality voice, using flexible movements of the pharyngeal cavity.

Note:Red circle is the epiglottis in the above photo.

The lips relevance to speaking smoothly

Does the movement of the lips affect speaking? The answer is No!
Words are primarily produced by the tongue. Please see the following figure.


You can see that the lips are not attached to the tongue. Therefore, there is no direct connection.
There is the orbicularis oris muscle, which is the soft tissue around the upper and lower lips, beside the platysma muscle, the buccinator muscle, the mentails, the depressor anguli oris muscle, the depressor labii inferioris muscle, the risorius, the zygomatic muscles, the levator anguli oris, the levator labii superioris and depressor septi nasi muscle.


These muscles move intricately, and the lips only articulate at the end of production.
The movement of the lips does not affect the speech or the ability to speaking smoothly.
In current research, we have found out that the movement of the suprahyoid muscles are the most important for speaking.
I previously described that there are no muscles that can move the larynx forward. Well, I’ve recently found out that this is not completely true.
If you can control the suprahyoid muscles smoothly, you can move the hyoid bone forward by using the genioglossus muscle.
I’m still investigating this fact and will keep you updated as the information develops.