Muscle hardness impairs rhythm and pitch

There is a high probability to having LDP, if your muscle hardness of the musculus extrinsic laryngis is more than 30 Tone.
LDP stands for “Larynx” “Deep” “Position.” Which is the habit of rigid muscles. It is a condition, not a disease. This next group research study is to find out whether LDP disturbs the rhythm and pitch of the voice, and how much or little muscle hardness will affect that vocalization.
I asked 5 people who have the measurement of muscle hardness less than 20 Tone, as well as 5 people who have the measurement of muscle hardness who are more than 30 Tone.
I chose 3 people to judge their singing and present a score for each of the 5 research study participants. The judges focused on observing 1:pitch 2:rhythm 3:expressiveness.
When comparing and analyzing their scores, It was shown that people who have less muscle hardness scored higher. People with less muscle hardness had more than double the score of the people that had more muscle hardness.
As a result, the conclusion is that hardened muscles (more than 30 Tone) relating to vocalization noticibly impaired singing.

Illustration of male throat anatomy

Note1:LDP obstructs the cricothyroid articulation, stopping it from moving in a widened range and letting out a high-pitched voice. You might have LDP even if you practice vocalizing so hard, and notice that you cannot let out a high-pitched voice.

Note2:LDP causes problems with the following
(1)narrow pitch range
(2)cannot keep/hold rhythm
(3)boxy voice
(4)shortness of breath
(5)easy to get a hoarse voice
(6)talking time to warm up the voice