The Voiceless alveolar fricative reference article from the English Wikipedia on 24-Apr-2004
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Voiceless alveolar fricative

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The voiceless alveolar fricative is a type of consonantal sound, used in some spoken languages. The symbol in the International Phonetic Alphabet that represents this sound is s, and the equivalent X-SAMPA symbol is s. The voiceless alveolar fricative occurs in English, and it is the sound denoted by the letter "s" in sit or pass.

IPA - Unicode s
IPA - image Image:Xsampa-s.png
X-SAMPA s
Sound sample

Features of this consonant: