PHONETICS MANUAL.indd - HumBox

Consonants like these are known either as STOPS (this term relates to the blockage
of the airflow in stage 1) or as PLOSIVES (this relates to the explosive release of air
in stage 3). But both terms refer to the same category of consonant: nowadays, stop
is used more often than plosive.
4.05 Fricatives
[s] and [z] don’t involve a complete obstruction of the airstream. The blade of the
tongue is held against the teethridge as for [t, d], but sufficiently loosely for the air to
be able to force its way through. Nonetheless, there is enough resistance at the point
of constriction for turbulence to be caused and a sound wave generated. So [s] and [z]
are examples of consonants with partial obstruction of the air-stream, and are known
as FRICATIVES (this term refers to the friction caused by the air as it passes through
the narrow gap).
The following diagram should make the difference between [t] and [s] clear. (The
voiced pair [d] and [z] would look the same, as voicing isn’t shown here.)
FIG. 29
Stop [t]
Fricative [s]
So now we can give a complete characterization of the sounds considered so far. This time
we specify (a) voicing, (b) place of articulation, AND (c) manner of articulation. Thus:
[s] is a voiceless alveolar fricative
[t] is a voiceless alveolar stop
[b] is a voiced bilabial stop.
Many other fricatives can be produced at various points along the vocal tract. In all
cases, the airstream is forced through a narrow channel or aperture, and there’s always
the same hissing or scraping effect.
Take for example [T] and [D]. The point of articulation is dental, but the manner
of articulation is fricative, not stop. You should easily be able to feel the air passing
between the tongue-tip and the back of the teeth, and the loose contact between them.
(With voicing added in the case of [ð] of course.)
Consonants
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