The sound or texture associated with the falsetto voice is produced by muscles (crico-thyroid and vocal cords) located in the laryngeal area in the throat. When the crico-thyroid muscle is mostly isolated, it gives us the sound called “falsetto.” The muscle produces this sound, which is responsible for lengthening and stretching the vocal cords to meet the pitch requirements.
Falsetto is half of our vocal instrument; needed to sing on pitch. Without this muscle active, developed, and coordinated with the closer muscle, we end up hurting ourselves through unhealthy acrobatics, as we try to make the other half of the voice do the work that was meant for the whole voice to do.
So, falsetto is necessary. And, it is not just a sound that men make when imitating a woman. Both men and women have a “falsetto voice” because both men and women have a crico-thyroid muscle from whence the falsetto texture arises.
The falsetto voice in its pure undeveloped state ranges from the B below middle C to the B above, is produced only on an [oo] vowel, has a duration of 2 or 3 seconds, and a high rate of breath expulsion. The crico-thyroid muscle, as it stretches the cords, also opens the cords. Thus, the need for the closer muscle to do its job if we can ever sing with economical use of the breath, as well as stability, volume, and power.
As the stretcher muscle or “falsetto” is exercised, there is coordination with the closer muscle. The coordination with the closer muscle means there is opposition, like when we lift weights. This opposition strengthens the falsetto, and it can be sustained for longer periods. One can sing an [i], [e], [oh] and finally an [ah] vowel, as well as consonants and words. The cords close more and check the airflow. The range extends. The falsetto gains the ability to have vibrato.
We can sing in this falsetto voice, using it for beautiful effect. The crico-thyroid muscle system responsible for producing falsetto can also coordinate with the arytenoid muscle system to bring the cords into a balanced equilibrium, providing us with a beautiful full voice.