Falsetto
Commonly cited in the context of singing, falsetto, a characteristic of phonation by both sexes, is also one of four main spoken vocal registers recognized by speech pathology.
Production of the normal voice involves vibration of the entire vocal cord, with the glottis opening first at the bottom and then at the top.
[6] William Vennard describes this process as follows: With the vocalis muscles relaxed it is possible for the cricothyroids to place great longitudinal tension upon the vocal ligaments.
[9]In the modal register, the vocal folds (when viewed with a stroboscope) are seen to contact with each other completely during each vibration, closing the gap between them fully, if just for a very short time.
When the air pressure in the trachea rises as a result of this closure, the folds are blown apart, while the vocal processes of the arytenoid cartilages remain in apposition.
The folds are covered on the surface by laryngeal mucous membrane, which is supported deeper down underneath by the innermost fibres of the thyroarytenoid muscle.
Some speakers and singers leave the cartilaginous portion of the glottis open (sometimes called 'mutational chink'), and only the front two-thirds of the vocal ligaments enter the vibration.
Some pioneers in vocal pedagogy, like Margaret Green and William Vennard, were quick to adopt current scientific research in the 1950s, and pursued capturing the biological process of female falsetto on film.
[13] In a book by GB Mancini, called Pensieri e riflessioni written in 1774, falsetto is equated with "voce di testa" (translated as 'head voice').
[13] The falsetto register is used by male countertenors to sing in the alto and occasionally the soprano range and was the standard before women sang in choirs.
Falsetto is occasionally used by early music specialists today and regularly in British cathedral choirs by men who sing the alto line.
[14] There is a difference between the modern usage of the "head voice" term and its previous meaning in the renaissance as a type of falsetto, according to many singing professionals.
[citation needed] Modal voice is capable of producing much more complex waveforms and infinite varieties of tone color.
[citation needed] Falsetto, however, does involve less physical effort by the singer than the modal voice and, when properly used, can make possible some desirable tonal effects.
[25] Some people who speak frequently or entirely in the falsetto register are identified by speech pathologists as suffering from a functional dysphonia.
[21] Falsetto also describes the momentary, but often repeated, fluctuations in pitch emitted by both sexes while undergoing voice change during adolescence.
