Vocal fry

The vocal fry register (also known as pulse register, laryngealization, pulse phonation, creak, croak, popcorning, glottal fry, glottal rattle, glottal scrape, or strohbass) is the lowest vocal register and is produced through a loose glottal closure which will permit air to bubble through slowly with a popping or rattling sound of a very low frequency. During this phonation, the arytenoid cartilages in the larynx are drawn together which causes the vocal folds to compress rather tightly and become relatively slack and compact. This process forms a large and irregularly vibrating mass within the vocal folds that produces the characteristic low popping or rattling sound when air passes through the glottal closure. The register (if well controlled) can extend far below the modal voice register, in some cases up to 8 octaves lower, such as in the case of Tim Storms who holds the world record for lowest frequency note ever produced by a human, a G−7, which is only 0.189 Hz. Humans however can only hear sounds down to 12 Hz under ideal conditions.

The vocal fry register has been a recognized and identifiable register in American English only within the past few decades, but its characteristic sound was recognized much earlier. Discussion of the vocal fry or pulse register began first within the field of phonetics and speech therapy and did not enter the vocabulary of vocal music pedagogists until the early 1970s, when it was initially controversial. However, the controversy surrounding the term within vocal music has subsided as more research into the use of the vocal fry register within the context of singing ensued. In particular, vocal pedagogist Margaret Greene's videotaping of the physiological processes occurring in the body while singers were phonating in the vocal fry register offered solid evidence that this type of vocal phonation should be considered a vocal register within both a speech pathology and vocal music perspective. As with any other vocal register, the vocal fry register has a unique vibratory pattern of the vocal folds, a certain series of pitches, and a certain type of sound that distinguishes it from other vocal registers.

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