Features of the voiceless alveolo-palatal fricative:
Its manner of articulation is sibilantfricative, which means it is generally produced by channeling air flow along a groove in the back of the tongue up to the place of articulation, at which point it is focused against the sharp edge of the nearly clenched teeth, causing high-frequency turbulence.
Its phonation is voiceless, which means it is produced without vibrations of the vocal cords. In some languages the vocal cords are actively separated, so it is always voiceless; in others the cords are lax, so that it may take on the voicing of adjacent sounds.
It is an oral consonant, which means air is allowed to escape through the mouth only.
It is a central consonant, which means it is produced by directing the airstream along the center of the tongue, rather than to the sides.
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