Introduction To Phonetics

Introduction To Phonetics
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Phonetics is the branch of linguistics that
examines sounds in a language. Phonetics
describes these sounds using the symbols of
the International Phonetic Alphabet ( IPA).
The IPA uses a single symbol to
desribe each sound in a
language. If a letter in a word is
silent, there will be no IPA
symbol used in the
transcriptions.
~~~
The IPA can be helpful for studying a
language, especially languages that use
letters that are silent or have multiple
pronunciations. Languages like Arabic and
Spanish are consistant in their spelling and
pronunciation – each letter represents a
single sound which rarely varies. English is
different. It has many letters with two or
more sounds and many letters that are
silent.
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Phonetics: vowels
~~~~~~~~~~~~
This table shows English vowel sounds with
IPA symbols ( International Phonetic
Alphabet ) and standard symbols ( std ). The
words in parentheses represent the IPA
transcription. Standard symbols are used in
most English dictionaries.
For each sound there is a word that
demonstrates where the sound occurs (word
initial, middle, or word final) and how the
sound occurs (what letter or letter
combinations). Click on the words to get an
idea of these sounds. Pay attention to the
sound of the letters in bold .
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#Phonetics
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An Introduction to Speech
Production
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OVERVIEW OF SPEECH GENERATION
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Speech is achieved by compression of the
lung volume causing air flow which may be
made audible if set into vibration by the
activity of the larynx. This sound can then
be made into speech by various
modifications of the supralaryngeal vocal
tract.
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LUNG STRUCTURE AND FUNCTION
Expanding the thoracic cavity by expanding
the rib cage (raising the ribs) and by
lowering the diaphragm increases lung
volume, decreases air pressure in the lungs
and so air is drawn in from the from the
outside to equalise pressure. Contracting the
thoracic cavity by contracting the rib cage
(lowering the ribs) and by raising the
diaphragm decreases lung volume, increases
air pressure in the lungs and so air is
expelled from the lungs to equalise pressure
with the outside air.
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LARYNX STRUCTURE AND FUNCTION
~~~~~~~~
The larynx is a continuation of the trachea
but the cartilage structures of the larynx are
highly specialised. The main cartilages are
the thyroid, cricoid and arytenoid cartilages.
These cartilages variously rotate and tilt to
affect changes in the vocal folds. The vocal
folds (also known as the vocal cords)
stretch across the larynx and when closed
they separate the pharynx from the trachea.
When the vocal folds are open breathing is
permitted. The opening between the vocal
folds is known as the glottis. When air
pressure below closed vocal folds (sub-
glottal pressure) is high enough the vocal
folds are forced open, the vocal folds then
spring back closed under both elastic and
aerodynamic forces, pressure builds up
again, the vocal folds open again, ... and so
on for as along as the vocal folds remain
closed and a sufficient sub-glottal pressure
can be maintained. This continuous periodic
process is known as phonation and produces
a "voiced" sound source.
Different laryngeal adjustments affect the
way that the vocal folds vibrate and can
result in different voice qualities, some of
which are important linguistically in some
languages.
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ARTICULATION
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When sound is produced at the larynx, that
sound can be modified by altering the shape
of the vocal tract above the larynx
(supralaryngeal or supraglottal). The shape
can be changed by opening or closing the
velum (which opens or closes the nasal
cavity connection into the oropharynx), by
moving the tongue or by moving the lips or
the jaw.