In last two issues we discussed about five consonant sounds.
/p/ voiceless, bilabial and plossive
/b/ voiced, bilabial and plossive
/m/ voiced, bilabial and plossive
/θ/ voiceless, dental and fricative
/ð/ voiced, dental and fricative
In this article we shall discuss the terms ‘ phonetics ‘and ‘ phonology ‘ and phonetic descriptions of speech sounds.
Phonetics is the study of speech sounds. Every language uses a limited number of speech sounds and makes its own selection out of the large number of different sounds the human vocal organs can produce. Phonetics is concerned with the description and classification of these sounds on the basis of how they are produced by our vocal organs and how they are perceived by our hearing mechanism.
Phonology is concerned with how particular language organises its sounds into distinctive units ( called phonemes), how the phonemes are combined into syllables, and how the prosodic features of length , stress and pitch are organised into patterns.
The production of speech : The speech mechanism
A Speech Operation
The transmission in sound of the simplest concept in the mind is the result of a complicated chain of events. Any speech operation depends on a chain of speech acts. An effective act of speech is an exceedingly complex operation involving a number of operations. The first stage is psychological ,the second is physiological and third is physical. First of all a concept is formulated in the speaker’s brain and human nervous system transmits this linguistic message to the so -called organs of speech, articulatory or physiological. The organs of speech are thus activated and their movements create disturbances in the air; and these sound waves are received by the listener’s ears. And at the listener’s end , first of all the ears receive the linguistic codification; the nervous system passes this linguistic message to the brain, where the linguistic interpretation of the message takes place.
The linguistic message conveyed to the organs of speech by the nervous system activates the lungs, larynx and the cavities in such a way that they perform a series of movements to produce a particular pattern of sound. For the production of speech we need an air -stream mechanism .( For the sounds of English we make use of an egressive pulmonic air- stream, that is, the air pushed out of the lungs through the mouth or nose or both. Generally all speech -sounds are made by an egressive pulmonic air stream of outgoing breath, although in a few languages (such as Hottentot -Nama - Khoekhoe) , there are speech sounds often called “clicks” which are made on ingressive (in going )air.
In this way the speech- sound is produced by the articulatory movements in the chest ,throat, mouth and nose. The articulatory apparatus has four areas: 1) the larynx containing the vocal cords 2) the oral cavity (mouth) 3) the pharyngeal cavity (throat) and 4) the nasal cavity (nose). The airstream coming from the lungs may be modified in any of these areas in a variety of ways. Such modification results from some kind of interference with the movement of the air stream. The most important roles are played by the vocal cords, soft palate,tongue , lips, teeth and nose.
The role of each speech organ in the production of speech:
1) The Diaphragm and Lungs:
The diaphragm is situated in the human body below the lungs and controls the expansion and contraction of the lungs in breathing. It is involved in the production of chest- pulses on which the division of syllables is based. The lungs serve as a source for air, which passes upward through the wind- pipe and larynx consisting of the vocal cords on the mouth or nose or both and comes outwards. The source of energy for the production of speech is generally the air-stream coming out of the lungs. It is certainly so in the case of all sounds used in Gujarati, Hindi and English.
2) The Larynx and Vocal Cords :
The larynx is the little box that is popularly called the Adam’s apple. It is a casing , formed of of cartilage and muscle, a bony box like structure in the front of the throat, situated in the upper part of the wind- pipe or the trachea ,containing valve like opening consisting of two membranous tissues, the vocal cords . The vocal cords are like a pair of lips placed horizontally from front to back. They are joined in the front but can be separated at the back and the opening between them is called glottis. When we breathe in and out the glottis is open. This is the position of production of The breathed or voiceless sounds. For example / p/ , / t/ , /k/ ,/f/ /s/ as in the English words pen , teacher, kite, fan , save . The glottis may be held tightly closed to produce a glottal stop or glottal catch (such as the speakers of English make between the two oh’s of “oh- oh” when said in surprise for reproof). The glottis may be held open in such a way that, when the air is passed through with sufficient energy, there is audible glottal friction as in /h/.
The major role of the vocal cords is that of a vibrator in the production of voice or phonation . If the vocal cords are held loosely together , the pressure of the air coming from the lungs makes them vibrate: that is, the open and close regularly many times a second. This vibration of the vocal cords produces a musical not called voice, and sounds produced in this way are called voiced- sounds . For example, all vowel sounds and the consonants /b,d, g,v, z, m, n, l / in English words book , dog , goat ,van ,zebra, man , nest, list are voiced.
The number of times the vocal cords open and close in one second is known as the frequency of vibration, and determines the pitch of the voice. Whereas tension of the vocal cords determines the pitch ,the force with which air is passed out from the lungs, determines the volume of a sound.
3) The soft palate :
The roof of the mouth has three parts : the hard convex surface just behind the upper front teeth called the alveolar or the teeth ridge; hard concave surface behind it called the hard palate ; and the soft palate at the back ,with the uvula at its end.
The soft palate can be moved up to block the passage into the nose. The air from the lungs then has to come out through the mouth only/the sounds produced/ in this way are called oral sounds. All English sounds except/m, n, Å‹/ are oral sounds. If the soft palate is lowered and passage through the mouth is closed, the air from the lungs comes out through both the mouth and nose . Sounds produced in this manner are called nasal sounds. For example, /m, n, Å‹/ in English words mango, nest and king.
4) The Tongue:
Of all the movable organs within the mouth, the tongue is by far the most fleecy, and is capable of assuming a great variety of positions in the articulation of both vowels and consonants. The tongue ,for the convenience of description has four parts: the tip, the blade ,the front and the back. It is the position of the tongue which is largely responsible for the difference in the sounds of various vowels. The extreme end of the tongue is called the tip. The part of the tongue opposite the alveolar ridge is called the blade, the part opposite the hard palate is called the front, and the part opposite the soft palate is called the back.
5) The Lips:
The position of lips affects very considerably the shape of the total cavity. They may be shut or held apart in various ways. When they are held lightly shut, they form a complete obstruction to produce bilabial stops, e g. / p ,b/ .
Today we will discuss two more phonemes: /f,v/ .
/f/ During the articulation of /f/ the lower lip is brought very close to the upper front teeth so that the gap between them is extremely narrow. The soft palate is raised and thus the nasal passage of air is blocked completely. The air escapes through the narrow gap between the lower lip and the upper front teeth with audible friction. The vocal cords are held wide apart and they do not vibrate. /f/ is thus a voiceless, labio- dental , fricative.
Spellings: /f/is represented by
i) the letter f as in food, four
ii) the letters ff as in coffee, affect
iii) the letters ph as in photo, , phonetics
iv) the letters gh as in cough, tough
/f/ can occur initially, medially and finally as:
fine
fill word initial/f/
first
office
lift word medial/f/
coffee
roof
calf word final/f/
tough
/f/ should be clearly distinguished from aspirated/p/ ( that is,ph ) to avoid confusion between words like
fair and pair
full and pool
/v/ is articulated adjective like /f/ described above except that during the articulation of /v/ the vocal cords vibrate producing voice why does a voice. /v/ is thus voiced, labio- dental fricative
Spellings: /v/ is represented by
i ) the letter v as in over
ii) the letter f as in of
iii) the letters ph as in nephew
Distribution:
/v/ occurs initially, medially and finally as
vine
van word initial/v/in
vice
ever
cover word medial/v/
over
live
love word final/v/
move
Most Indians speakers replace /v/ by soft frictionless sound /V/ which is hardly audible to native speakers of English. For international standards the fricative/v/ should be learnt. It can be produced by adding voice to /f/.
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