Sibilant consonant
From Freepedia
A sibilant, or a strident fricative, is a type of fricative or affricate, made by speeding up air through a narrow channel and directing it over the sharp edge of the teeth.
Sibilants are louder than their non-sibilant counterparts, and most of their acoustic energy occurs at higher frequences than non-sibilant fricatives. [s] has the most acoustic strength at around 8,000 Hz, but can reach as high as 10,000 Hz. [ ʃ ] has the bulk of its acoustic energy at around 4,000 Hz, but can extend up to around 8,000 Hz.
Of the sibilants, the following have IPA symbols of their own:
- ɕ, ʑ (Alveolo-palatal: that is, laminal palatalized postalveolar; these are equivalent to ʃʲ, ʒʲ)
Diacritics can be used for finer detail. For example, apical and laminal alveolars can be specified as [s̺] vs [s̻]; a dental (or more likely denti-alveolar) sibilant as [s̪]; a palatalized alveolar as [sʲ]; and a generic postalveolar as [s̠], a transcription frequently used when none of the above apply (that is, for a laminal but non-palatalized, or "flat", postalveolar).
Only the alveolar and palato-alveolar sibilants are distinguished in English; the former are apical, while the latter are slightly labialized and generally called simply "postalveolar": [s̺ z̺] [ʃʷ̜ ʒʷ̜]. Polish and Russian have laminal denti-alveolars, palatalized denti-alveolars, flat postalveolars, and alveolo-palatals, [s̪ z̪] [s̪ʲ z̪ʲ] [s̠ z̠] [ɕ ʑ]; whereas Mandarin has apical alveolars, flat postalveolars, and alveolo-palatals, [s̺ z̺] [s̠ z̠] [ɕ ʑ]. Few languages distinguish more than three series of sibilants without secondary articulation, but Ubykh has four series of plain sibilants, and the Chinese dialect of Qinan, in Shandong province, is said to have five. Toda has a laminal alveolar, an apical postalveolar, laminal domed postalveolars, and sub-apical palatals. Since two of these could be called 'retroflex', Ladefoged & Maddieson 1996 have resurrected the old IPA diacritic for retroflex, the underdot, for apical retroflexes, and reserve the letters <ʂ, ʐ> for sub-apical retroflexes. Thus the Toda sibilants can be transcribed [s̪] [ṣ] [ʃ̻ ʒ̻] [ʂ ʐ], although the official IPA symbols [s̪] [s̠] [ʃ̻ ʒ̻] [ʂ ʐ] are also sufficient. (In some publications the underdot and underbar are interchanged.)
Some authors, as for instance Chomsky & Halle (1964), group [ f ] and [ v ] as sibilants. However, they do not have the grooved articulation and high frequencies of other sibilants, and most phoneticians (for instance by Ladefoged & Maddieson 1996), continue to group them together with the bilabial fricatives [ ɸ, β ] as non-sibilant anterior fricatives.
