A vocal register is a collection of pitches produced people’s voices. Because the vocal cords function in the same basic way, or have the same fundamental pattern of vibration, for each note in the register, and because the pitches cause the same areas of the body to resonate, the pitches all have the same quality.
People who have studied vocal production have identified as many as seven distinct registers in the voice, but only four are widely accepted. The vocal fry register, which is the lowest of the registers, is the first. The vocal cords are very loosely closed in this register, and air bubbles through with a rattling quality. In most cases, this register is not used in singing, but it is used in a few instances.
The modal register is the second vocal register, and it is where people usually talk and sing when they are at ease. The entire vocal cord set closes in this register. This register’s tones are typically clear and carry well, and the vocalist can produce them without strain. The modal register is where most vocal training for singing takes place.
The falsetto register is located above the modal vocal register. The falsetto is distinguished from the modal register the fact that only the thin edges of the vocal cords vibrate. This register has a more breathy quality to it, and it’s often compared to a flute.
The whistle register is the final vocal register, named for its whistle-like sound. In most cases, only women produce tones in this range. At least two-thirds of the cords should be closed, leaving only a small opening for air to pass through. Some singers can naturally reach this range, but most of the time, some practice is required to avoid straining and damaging the vocal cords.
Instead of four registers, some singing instructors divide the voice into three: a chest register corresponding to the modal register, a middle voice, and a head voice. Men’s voices have a chest, head, and falsetto register, while women’s voices have a chest, middle, and head register. As a result, there has been some confusion about which register is which. Depending on gender, “head register” could refer to the middle or upper part of the voice. This is especially perplexing because some people define “head register” or “head voice” as the upper part of the modal register where resonance vibration occurs primarily in the head.
The break, or more properly, the passaggio, is the point at which a person changes from one register to another, regardless of whether the voice is divided into three or four registers. Due to the presence of multiple vocal registers, people have multiple passaggios. Singers are frequently concerned about how to transition from one register to another, particularly when they are learning.
One important point to remember about vocal registers is that the point at which people switch from one to the next is not always the same. Because no two people have the same physiology, the vocal break cannot be the same for everyone. Many different voice types exist based on the structure of the cords and surrounding tissues. Most people, however, break within a fairly predictable range, as vocal teachers and pathologists have discovered. A soprano, for example, usually has a register break between E5 and G5.
From a variety of perspectives, knowing roughly where a break occurs between vocal registers is critical. Teachers and students use their knowledge to work around the break, adjusting resonance to create a more seamless sound between registers and the illusion of a single continuous range for the singer. Similarly, when writing music, composers consider the typical break range carefully. They understand that series of pitches, especially melismatic ones that require a high level of vocal agility, are more difficult to get through near the break points.