Phonetics

2. Phonetics

2.1 What is phonetics?

Phonetics is defined as the study of the phonic medium of lan­guage; it is concerned with all the sounds that occur in the world's languages.

Phonetics includes articulatory phonetics, auditory phonetics, and acoustic phonetics.  Articulatory phonetics studies the sounds from the speaker's point of view. It is concerned with how a speaker uses his speech organs to articulate the sounds. Auditory phonetics looks at the sounds from the hearer's point of view. It  studies how the sounds are perceived by the hearer. Acoustic phonetics studies the way sounds travel and the physical means by which sounds are transmitted. By studying the sound-waves or physical properties of sounds recorded, linguists have come to some important conclusions. For example, the repetitions of what might be heard as the same utterance are physically identical only by coincidence. What sounds to be identi­cal to our ear is actually not so. Therefore, phonetic identity is a the­oretical ideal.

2.2 Organs of speech

The articulatory apparatus of a human being, are contained in three important areas or cavities: the pharyngeal cavity --- the throat, the oral cavity --- the mouth, and the nasal cavity --- the nose.

 The pharyngeal cavity

 Air coming from the lungs and through the windpipe passes through the glottis, a part of the laryax, which is a bony structure at the end of the windpipe. Lying across the glottis are the vocal cords. Vibration of the vocal cords results in a quality of speech sounds called voicing, which is a feature of all vowels and some consonants. such as [ b ], [ z ], and [m]. The speed of the vibration determines the pitch of the sounds. When the vocal cords are drawn wide apart, letting air go through without causing vibration, the sounds produced in such a condition are voiceless, such as [t], [s], and [f] in English.

The oral cavity

1. lips   2. teeth   3. teeth ridge (alveolus) 4. hard palate 5. soft palate (velum) 6. uvula 7. tip of tongue      8. blade of tongue 9. back of tongue        10. vocal cords  11.  pharyngeal cavity     12. nasal cavity

Oral cavity is the place where the greatest source of modification of the air stream is found. The main places involved are the back, the front, and the blade of the tongue, and also its extreme front --- the tip, the uvula, the soft palate (the velum), the hard palate, the teeth ridge (the alveolus), the teeth and the lips. Of all these, the tongue is the most flexible, and is responsible for more varieties of articulation than any other.  

                          

The nasal cavity                     

The nasal cavity is connected with the oral cavity. The soft part of the roof of the mouth, the velum, can be drawn back to close the passage so that all air exiting from the lungs can only go through the mouth. The sounds produced in this condition are not nasalized. The passage can also be left open to allow air to exit through the nose. In this case, the sounds pronounced are nasalized.

2.3 Orthographic representation of speech sounds --- broad and narrow transcriptions

Interna­tional Phonetic Alphabet (IPA) is a standardized and internationally accepted system of phonetic transcription. The basic principle of the IPA is using a different letter for each distinguishable speech sound. The transcriptions are divided into broad transcription and narrow transcription. The transcription with letter-symbols only is broad transcription, while the transcription with letter-symbols together with the diacritics to make finer distinc­tions is narrow transcription.

Here are some examples to show how the two transcriptions dif­fer.

In broad transcription, the symbol "t" is used for the sound [t] in words like star[sta:] and tar[ta:]. In narrow transcription, we use [sta:] and tar[t^ha:] to make finer distinctions.

2.4 Classification of English speech sounds

The speech sounds in the English language can be divided into vowels and consonants. The basic difference between a vowel and a consonant is that in the pronunciation of the former the air that comes from the lungs meets with no obstruction of any kind in the throat, the nose, or the mouth, while in that of the latter it is obstructed in one way or an­other.

2.4.1 Classification of English consonants

English consonants can be classified either in terms of manner of articulation or in terms of place of articula­tion.

In terms of manner of articulation:

stops:  When the obstruction created by the speech organs is total or complete, the speech sound produced with the obstruction audibly released and the air passing out again is called a stop or a plosive. The English stops fall into three pairs: [p] [b], [t] [d], and [k] [g],

fricatives:  When the obstruction is partial and the air is forced through a narrow passage in the mouth so as to cause definite local friction at the point, the speech sound thus produced is a fricative. The fricatives in English are[f] [v] [s] [z] [W] [T] [F] [V] [h].

Affricates: When the obstruction, complete at first, is released slowly with the friction resulting from partial obstruc­tion (as in fricatives), the sounds thus produced are affricates. In English there are two affricates [tF] and [dV].

Liquids: When the airflow is obstructed but is allowed to es­cape through the passage between part or parts of the tongue (the tip or the sides ) and the roof of the mouth, the sounds thus produced are called liquids. The English liquids are [ 1 ] and [ r ]. [ 1 ] is called a lateral sound because in the production of it the sur­face of the tongue, instead of being more or less flat, is made slightly convex and causes stoppage in the centre of the roof of the mouth while allowing air to pass at the sides. In the production of the other liquid [r], the tip of the tongue is curled back and the air passes over it. It is also called "retroflex."

Nasals: When the nasal passage is opened by lowering the soft palate at the back of the mouth and air is allowed to pass through it, the sounds thus produced are called nasals. There are three nasals in English [ m ] [ n ] and [N].

Glides, sometimes called " semivowels," are a rather marginal category. The English glides are [w] and [j], both voiced. They are formed in the same man­ner as the vowels [u] and [i], with a narrower passage between the lips or between the tongue and the hard palate to cause some slight noise from the local obstruction.

In terms of place of articulation:

bilabial:  In the production of these sounds, the upper and the lower lips are brought together to create obstruction. The English bilabials are [p] [b] [m] [w].

labiodental:  In the production of these sounds, the lower lip is brought into contact with the upper teeth, thus creat­ing the obstruction. The labiodental sounds in Eng­lish are [f] and [v].

dental: The obstruction is created between the tip of the tongue and the upper teeth. There are two dental sounds in English; they are [W] and [T].

alveolar:  The tip of the tongue is brought into contact with the upper teeth-ridge to create the obstruction. The alve­olar sounds are [t] [d] [s] [z] [n] [1] [r]

palatal:  The obstruction is between the back of the tongue and the hard palate. The palatal sounds are [F] [V] [tF] [dV] [j].

velar: The back of the tongue is brought into contact with the velum, or the soft palate. The sounds thus pro­duced in English are [k] [g] and [N].

glottal:  The vocal cords are brought momentarily together to create the obstruction. There is only one glottal sound in English, i.e. , [h].

2.4.2 Classification of English vowels

Vowel sounds are classified according to: the position of the tongue in the mouth, the openness of the mouth, the shape of the lips, and the length of the vowels.

1) the position of the tongue in the mouth

Front vowels are the ones in the production of which the front part of the tongue is raised the highest such as [i:] [i] [e] [A] [a].

When the central part of the tongue maintains its highest position, the vowels thus produced are central vow­els such as  [3:] [E] and [Q] .

If the back of the tongue is held the highest, the vowels thus produced are  back vowels such as [u:] [u] [C:] [R] and [B:].

2)the openness of the mouth

close vowels: [i:] [i] [u:] and [u];

semi-close vowels: [e] and [3;]

semi-open vowels: [E] and [R:]

open vowels: [A] [a] [Q ] [ C ] and [ B: ].

3) the shape of the lips

  rounded vowels: All the back vowels in English are rounded except [ɑ:].

  unrounded vowels: All the front vowels and central vowels in English are unrounded.

4)the length of vowels

 long vowels: They are usually marked with a colon such as[i:] [\:] [ C: ] [u:] [ɑ:]

 short vowels: Except [i:] [\:] [ C: ] [u:] [ɑ:], other vowels in English are short vowels.

5) the state of tension

  tense vowels: The long vowels are all tense vowels.

  loose vowels:The short vowels are lax vowels.

With these criteria, we can easily describe English vowels. For example, the vowel [e] can be de­scribed as front, semi-close, and unrounded.

So far we have been classifying the individual vowels, also known as monophthongs. In English there are also a number of diph­thongs, which are produced by moving from one vowel position to another through intervening positions. The diphthongs include [ei] [ai] [Eu] [au] [Ci] [iE] [eE][uE].