As a linguistics expert with a deep understanding of phonetics and phonology, I can provide a comprehensive explanation of what stridents are in the context of English phonetics.
Stridents are a class of consonants that are characterized by the friction created when air is forced through a narrow channel made by the articulatory organs. In English, stridents include sounds like /f/, /v/, /s/, /z/, /ʃ/, /ʒ/, /θ/, and /ð/. These sounds are produced by narrowing the oral cavity and creating turbulence as the air passes through the vocal tract.
One of the key features of stridents is that they involve a high degree of constriction in the vocal tract, which leads to audible friction. This friction is what gives stridents their distinctive "hissing" or "buzzing" quality. For example, the sound /s/ in the word "snake" or the sound /z/ in the word "zoo" are both produced with a significant narrowing of the vocal tract and a strong burst of air.
Another important aspect of stridents is their place of articulation. The place where the constriction occurs in the vocal tract can vary, leading to different types of stridents. For instance, /s/ and /z/ are alveolar stridents, produced with the tip of the tongue close to the alveolar ridge (the bumpy area behind the upper front teeth). On the other hand, /ʃ/ and /ʒ/ are palato-alveolar stridents, produced with the middle part of the tongue raised towards the hard palate.
The term "sibilants" is sometimes used interchangeably with "stridents," but there is a subtle difference. Sibilants are a subset of stridents that are specifically characterized by a high-pitched, hissing sound. In English, the sibilants are /s/, /z/, /ʃ/, and /ʒ/. The sounds /f/ and /v/, while they are stridents, are not typically classified as sibilants because they tend to have a lower pitch and are not as hissy as the other sibilants.
It's also worth noting that the perception of stridents can be influenced by the context in which they are spoken. For example, the sound /s/ can be realized as a voiceless dental fricative [s] when it appears at the beginning of a word or before certain consonants, but it can be realized as a voiceless alveolar fricative [ʃ] when it appears before /j/ as in the word "measure."
In summary, stridents are a class of consonants in English that are defined by the friction created when air is forced through a narrow channel in the vocal tract. They are characterized by a high degree of constriction and a distinctive hissing or buzzing quality. The English stridents include /f/, /v/, /s/, /z/, /ʃ/, /ʒ/, /θ/, and /ð/. While sibilants are a subset of stridents, not all stridents are sibilants due to differences in pitch and the quality of the hissing sound they produce.
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The English stridents are /f, v, s, z, ?, ?, t?, d?/. ... The English sibilants are /s, z, ?, ?, t?, d?/. On the other hand, /f/ and /v/ are stridents, but not sibilants, because they are lower in pitch.read more >>