Indiscriminate use of the word register has led to much confusion and controversy about the number of registers in the human voice within vocal pedagogical circles.
Modal voice register：真声。
The first of these vibratory forms is known as natural or normal voice; another name for it is modal voice, a term currently widely used in both speech pathology and vocal pedagogy publications. In this usage, modal refers to the natural disposition or manner of action of the vocal cords.
The essential difference between the modal and falsetto registers lies in the amount and type of vocal cord involvement. The falsetto voice is produced by the vibration of the ligamentous edges of the vocal cords, in whole or in part, and the main body of the fold is more or less relaxed. In contrast, the modal voice involves the whole vocal cord with the glottis opening at the bottom first and then at the top.
The contemporary use of the term chest voice often refers to a specific kind of vocal coloration or vocal timbre. In classical singing, its use is limited entirely to the lower part of the modal register or normal voice.
Clippinger claims that males and females switch registers at the same absolute pitches. He also states that at about E flat or E above middle C the tenor passes from what is usually called open to covered tone, but which might better be called from chest to head voice. At the same absolute pitches the alto or soprano passes from the chest to the middle register. According to Clippinger there is every reason to believe that the change in the mechanism for male voices into head register is the same as that which occurs in the female voice as it goes into the middle register at the same pitches.