Five-octave vocal range

Vocal range is the measure of the breadth of pitches that a human voice can phonate. Its most common application is within the context of singing, where it is used as a defining characteristic for classifying singing voices into groups known as voice types. It is also a topic of study within linguistics, phonetics, and speech and language pathology, particularly in relation to the study of tonal languages and certain types of vocal disorders, although it has little practical application in terms of speech.

While the broadest definition of "vocal range" is simply the span from the lowest to the highest note a particular voice can produce, this broad definition is often not what is meant when "vocal range" is discussed in the context of singing. Vocal pedagogists tend to define the vocal range as the total span of "musically useful" pitches that a singer can produce. This is because some of the notes a voice can produce may not be considered usable by the singer within performance for various reasons. For example, within opera all singers must project over an orchestra without the aid of a microphone. An opera singer would therefore only be able to include the notes that they are able to adequately project over an orchestra within his or her vocal range. In contrast, a pop artist could include notes that could be heard with the aid of a microphone.

Another factor to consider is the use of different forms of vocal production. The human voice is capable of producing sounds using different physiological processes within the larynx. These different forms of voice production are known as vocal registers. While the exact number and definition of vocal registers is a controversial topic within the field of singing, the sciences identify only four registers: the whistle register, the falsetto register, the modal register, and the vocal fry register. Typically only the usable pitches within the modal register—the register used in normal speech and most singing—are included when determining singers' vocal ranges. There are exceptions, as in opera, where countertenors employ falsetto and coloratura sopranos use the whistle register; notes from these registers would therefore be included in the vocal ranges of these voices.

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