Death grunt

A death growl (or simply a growl) is a vocal style (an extended vocal technique) usually employed by singers from death metal music genres, but also used in a variety of other heavy metal styles, such as metalcore. Death growls are sometimes criticized for their "ugliness". However, the harshness of death growls is in keeping with death metal's abrasive music style and often dark and obscene subject matter. The progressively more forceful enunciation of metal vocals has been noted from heavy metal to thrash metal to death metal.

Death metal, in particular, is associated with growled vocals. Death metal, which tends to be lyrically and thematically darker and more morbid than other forms of metal, features vocals that attempt to evoke chaos, death, and misery by being "usually very deep, guttural, and unintelligible". Natalie Purcell notes, "Although the vast majority of death metal bands use very low, beast-like, almost indiscernible growls as vocals, many also have high and screechy or operatic vocals, or simply deep and forcefully sung vocals." Sociologist Deena Weinstein has noted of death metal: "Vocalists in this style have a distinctive sound, growling and snarling rather than singing the words. Making ample use of the voice distortion box."

Death growls are also known as "death metal vocals", "guttural vocals", "death grunts", "growled vocals", "unclean vocals", "harsh vocals", and also jocularly as "Cookie Monster vocals."

Growls can be obtained with various voice effects, but the effects are usually used to enhance rather than create, and are seldom used at all. Voice teachers teach different techniques, but long-term use will still take its toll if done incorrectly – these techniques are designed to reduce rather than eliminate harm. However it has been shown by many vocalists (ex. Christian Älvestam) that long-term use of these techniques can occur without causing harm to the voice. The techniques usually involve using the diaphragm and air pressure on the throat to form the sound, similar to forms of overtone singing. As a person tries to squeeze their throat, the sound gets less intense (usually used for higher growls/screams to decrease tension on chords). Some vocalists (ex. Danny Worsnop, Oliver Sykes) tend to use too much pressure on their throats and thus have vocal cord problems/defects. The Radboud University Nijmegen Medical Centre in The Netherlands reported in June 2007 that, because of the increased popularity of growling in the region, it was treating several patients who had performed the techniques incorrectly for edema and polyps on the vocal folds.

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