Tips to learn Phonetics

Speech Mechanism and the Organs of Speech

Introduction

Phonetics:

     Phonetics is a branch of linguistics, which deals with the spoken language. It deals with the production, transmission and reception of the sounds produced at the time of speaking.

Types of phonetics:

     There are three types of phonetics. They are,

           

Phonetics Vs Phonology:

     Phonetics is the study of speech sounds of all languages in general.

     Phonology is the study of the sound system that applies to any particular language. For example, the study of the speech sounds of English language is phonology.

     Phonology involves the study of three things. They are,

i)        determining the distinctive sounds in a language

ii)      describing the changes that take place in these sounds and,

iii)    establishing the different positions in which these sounds can occur in connected speech.

The Air Stream Mechanism

     The production of any speech sound involves the moment of the air-stream mechanism. By altering the flow of air, we can produce different sounds. This will become evident in a simple experiment. Say a prolonged ‘ah’ in a whisper, place your palm in front of your mouth while saying ‘ah’, your palm will feel the warm air getting out of your mouth. When you say ‘ah’ and ‘baa’ alternatively for several times you will see the air escapes from your mouth, when you close your lips for  producing the ‘b’ of baa and the air continues to flow out when you open your lips.

Q. Discuss the air stream mechanism in detail. [10M]

Q. Explain the three air stream mechanisms. [10M]

Q. Define air-stream mechanism. [2M]

Q. What do you mean by Organs of Speech? [2M]          

     An air-stream is required for the production of speech sounds. The air that flows out of the mouth is modified into speech sounds by the action of certain organs of the body. These organs are commonly referred to as organs of speech. An air-stream, which is the basis of speech sounds, can also be called a moving current of air. Lung is air is used for the articulation of the most speech sounds.

Q. What are the types of air-stream mechanisms? [2 M]

     An air stream is produced by an air-stream mechanism works exactly like a flit-gun. In a flit-gun, a body of liquid is moved by working on apparatus called a Plunger. When the plunger is moved in one direction, the liquid is pulled in and when it is moved in the opposite direction, the liquid is pushed out. While speaking, something like a plunger in a flit-gun is in opposite and it is called the initiator. The air-stream is set in motion by the initiator, just as the liquid in a flit-gun is set in a motion by the plunger. There are three main air-stream mechanisms.

~  Pulmonic air-stream mechanism

~  Glottalic air-stream mechanism and

~  Velaric air-stream mechanism

Q. Explain Pulmonic air-stream mechanism. [5 M]

Q. What are egressive and ingressive? [2 M]

a) Pulmonic air-stream mechanism:

     The Pulmonic air-stream mechanism consists of the lungs and the respiratory muscles. The walls of the lungs act as the initiator. They are moved by the respiratory muscles so that the air is pulled out of them. This mechanism is used by a very large percentage of speech sounds in all the languages that are spoken in the world. When the air-stream mechanism is used to push air out, it is called as egressive pulmonic air-stream mechanism and when it is used to draw in, it is called ingressive air-stream mechanism.

     Most speech sounds make use of a pulmonic egressive air-stream mechanism. In fact all the sounds of English and most Indian languages are produced with this air-stream mechanism. No language uses pulmonic ingressive air-stream mechanism for the production of speech sounds. This mechanism is used while yawning and snoring.

Q. Explain Glottolic air-stream mechanism. [5 M]

b) Glottalic/ Pharyngeal air-stream mechanism:

     In this mechanism, the closed glottis acts as the initiator and the air in the pharynx is used. Hence, some linguists refer to this mechanism as Pharyngeal. Some language use both egressive and ingressive glottalic air-stream mechanisms. Among the Indian languages, Sindhi has sounds articulated with a Glottalic ingressive air-stream mechanism. These sounds are called implosives.

Q. Explain Velaric air-stream mechanism. [5 M]

c) Velaric air-stream mechanism:

     The back of the tongue is the initiator and the air in the mouth is set in motion during Velaric air-stream mechanism. Hence it is also known as oral air-stream mechanism. Sounds in several African languages are produced with Velaric ingressive mechanism. Sounds produced with a Velaric egressive air-stream mechanism do not seem to exist in any language.

Organs of Speech

Q. Elaborate on the organs of speech and its functions. [10M]

     In most of the language the production of speech sounds are produced with a Pulmonic egressive air-stream mechanism. The air that is breathed out comes out of the lungs. Before it gets out into the outer atmosphere, various organs of human body convert it into speech sounds. These organs are called organs of speech. The lungs, the vocal cords, the tongue, the teeth and the lips are some of the organs of speech. These organs, in addition to their primary functions, involve themselves in the production of speech sounds. Hence they are referred to as organs of speech.

Active and Passive Articulators:

     The most important organs of speech are those that are movable. The vocal folds (cords), soft palate, tongue and lips are termed as active articulators and the others are termed as Passive articulators. The tongue plays a prominent part in the modification of sounds. The word “language” itself is derived from the Latin word lingua meaning tongue. Based on their functions, the speech organs can be divided into the following three groups

[ The Respiratory System: it comprises the lungs, the muscles of the chest and the windpipe or Trachea.

[ The Phonatory System: this comprises the larynx.

[ The Articulatory system: this comprises the nose, the teeth, the tongue, the roof of the mouth and the

lips.

     The various organs which are involved in the production of speech sounds are called speech organs (also known as vocal organs). The study of speech organs helps to determine the role of each organ in the production of speech sounds. They include the lungs, the vocal folds, and most importantly the articulators. When we say a particular sound, a stream of air comes out of the lungs, passes through the respiratory tract and gets into the outer atmosphere through the mouth or the nose or through both.

The Respiratory System

1. The Lungs

     The airflow is by far the most vital requirement for producing speech sound, since all speech sounds are made with some movement of air. The lungs provide the energy source for the airflow. The lungs are the spongy respiratory organs situated inside the rib cage. They are made up of small sacs called alveoli. In alveoli, the blood is cleaned of its carbon-di-oxide (Co2) and provided with fresh oxygen from the outer-air. Air is supplied to the alveoli by small tubes called the bronchioles. The bronchioles come together into two large tube called bronchi, which is situated on the right and the left side. The bronchi join the trachea and passes through the throat into the lungs. The act is commonly known as respiration.

     Respiration involves two processes: (i) inspiration and (ii) expiration. Inspiration means taking outer air into the lungs and expiration means throwing outer air from the lungs into the outer atmosphere. 

The Phonatory System

2. The Larynx & the Vocal Folds (Cords)

     The larynx is colloquially known as the voice box. It is a box-like small structure situated in the front of the throat where there is a protuberance. For this reason the larynx is popularly called the Adam’s apple. This casing is formed of cartilages and muscles. It protects as well as houses the trachea (also known as windpipe, oesophagus, and esophagus) and the vocal folds (formerly they were called vocal cords). The vocal folds 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. The opening between them is called glottis. The glottis is considered to be in open state when the folds are apart. In fact when we swallow food or drink water, the vocal cords shut the glottis and thus prevent the food and water from entering the windpipe. When the folds are pressed together the glottis is considered to be in close state.

The vocal folds take different positions:

Wide Apart: When the folds are wide apart (open) in a “V” shape, the glottis is open and they do not vibrate. The sounds produced in such position are called breathed or voiceless sounds. For example, the first sounds in English words like /p/ in peel /f/ in fine, /θ/ in with, /s/ in seen.

Narrow Glottis: If the air is passed through the glottis when it is narrowed then there is an audible friction. Such sounds are also voiceless since the vocal folds do not vibrate. For example, in English /h/ is a voiceless glottal fricative sound.

Tightly Closed: The vocal folds can be firmly pressed together so that the air cannot pass between them. Such a position produces a glottal stop /      / (also known as glottal catch, glottal plosive).

Touched or Nearly Touched: The major role of the vocal folds is that of a vibrator in the production of speech. The folds vibrate when these two are touching each other or nearly touching. The pressure of the air coming from the lungs makes them vibrate. This vibration of the folds produces a musical note called voice. And sounds produced in such manner are called voiced sounds. In English all the vowel sounds and the consonants /v/ in Vine, /z/ in zoo, /m/ in measure, /n/ in need, /b/ in bread, /g/ in girl, /d/ in deed,/t/ in then, /j/, in judge, /w/ in well are voiced.

     Thus it is clear that the main function of the vocal folds is to convert the air delivered by the lungs into audible sound. The opening and closing process of the vocal folds manipulates the airflow to control the pitch and the tone of speech sounds. As a result, we have different qualities of sounds.

The Articulatory System:

3. The Articulators

     Articulators transform the sound into intelligible speech. They can be either active or passive. They include the pharynx, the teeth, the alveolar ridge behind them, the hard palate, the softer velum behind it, the lips, the tongue, and the nose and its cavity. Traditionally the articulators are studied with the help of a sliced human head figure like the following:

The Pharynx: The pharynx lies between the mouth and the food passage, that is, just above the larynx. It is just about 7cm long in the case of women and 8cm long in the case of men.

(ii) The Roof of the Mouth: The roof of the mouth is considered as a major speech organ. It is divided into three parts:

a. The Alveolar Ridge/Teeth Ridge: The alveolar ridge is situated immediately after the upper front teeth. The sounds which are produced touching this convex part are called alveolar sounds. Some alveolar sounds in English include: /t/d/.

b. The Hard Palate: The hard palate is the concave part of the roof of the mouth, it’s hard and bony. It is situated on the middle part of the roof.

c. The Velum or Soft Palate: The lower part of the roof of the mouth is called soft palate. It could be lowered or raised. When it is lowered, the air stream from the lungs has access to the nasal cavity. When it is raised the passage to the nasal cavity is blocked. The sounds which are produced touching this area with the back of the tongue are called velar sounds. For example: /k/g/.

(iii)Uvula:

     The fleshy structure hanging loose at the extreme end of the roof of the mouth is called the uvula.

     Among the other parts of the roof of the mouth, the soft palate gathers more importance. It acts like a valve in opening and closing the nasal passage of air. This soft palate is responsible for the production of oral and nasal sounds.

Q. Discuss the various positions of the soft palate during the production of oral, nasal and nasalized sounds. [5 M]

Position of soft palate during the production of oral sounds: [Ref. Fig.5]

U  If the soft palate is raised so that it touches the back wall of the pharynx, the passage into the nose is closed.

U  The air then cannot escape through the nose.

U  Sounds during the production of which the air escapes only through the mouth are called oral sounds.

U  All the sounds in the English words peel, bag, slow, date and bush are oral sounds.

U  The closure of the nasal passage of air by raising the velum is called the velic closure.

Position of soft palate during the production of nasal sounds: [Ref. Fig.6]

¥  If the soft palate is lowered, the passage into the nose is opened.

¥ With the soft palate lowered, if the passage into the mouth is blocked (either by closing the lips or by making the tongue touch firmly some part of the roof of the mouth) the air from the lungs will escape into the outer atmosphere only through the nose.

¥  Sounds during the production of which the air escapes only through the nose are called nasal sounds.

¥  The last sounds in the English words sum, sun and sing are nasal.

¥  By lowering the soft palate, a velic opening is effected and thus the nasal passage is opened.

Position of soft palate during the production of nasalised sounds: [Ref. Fig.7]

² There are certain sounds, during the production of which the soft palate is lowered thus the opening the nasal passage of air.

² But the oral passage of air is not blocked and thus both the oral and the nasal passages are open.

² The air from the lungs will then escape simultaneously through the nose and the mouth. Such sounds are called nasalized sounds. The last sound in the French word ‘bon’ is nasalized.

The Lips:

     The lips also play an important role in the matter of articulation. They can be pressed together or brought into contact with the teeth. The consonant sounds which are articulated by touching two lips each other are called bilabial sounds. For example, /p/ and /b/ are bilabial sounds in English. Whereas, the sounds which are produced with lip to teeth contact are called labiodental sounds. In English there are two labiodental sounds: /f/ and /v/.

     Another important thing about the lips is that they can take different shapes and positions. Therefore, lip-rounding is considered as a major criterion for describing vowel sounds. The lips may have the following positions:

a. Rounded: When we pronounce a vowel, our lips can be rounded, a position where the corners of the lips are brought towards each other and the lips are pushed forwards. And the resulting vowel from this position is a rounded one. For example, /ə ʊ/.

b. Spread: The lips can be spread. In this position the lips are moved away from each other (i.e. when we smile). The vowel that we articulate from this position is an unrounded one. For example, in English /i: /is a long vowel with slightly spread lips.

c. Neutral: Again, the lips can be neutral, a position where the lips are not noticeably rounded or spread. And the articulated vowel from this position is referred to as unrounded vowel. For example, in English /ɑ: / is a long vowel with neutral lips.

           

The Teeth: The teeth are also very much helpful in producing various speech sounds. The sounds which are made with the tongue touching the teeth are called dental sounds. Some examples of dental sounds in English include: /θ//ð/.

The Tongue: The tongue is divided into four parts:

            a. The tip: It is the extreme end of the tongue.

            b. The blade: It lies opposite to the alveolar ridge.

            c. The front: It lies opposite to the hard palate.

            d. The back: It lies opposite to the soft palate or velum.

     The tongue is responsible for the production of many speech sounds, since it can move very fast to different places and is also capable of assuming different shapes. The shape and the position of the tongue are especially crucial for the production of vowel sounds. Thus when we describe the vowel sounds in the context of the function of the tongue, we generally consider the following criteria:

i) Tongue Height: It is concerned with the vertical distance between the upper surface of the tongue and the hard palate. From this perspective the vowels can be described as close and open. For instance, because of the different distance between the surface of the tongue and the roof of the mouth, the vowel /i: /has to be described as a relatively close vowel, whereas /æ / has to be described as a relatively open vowel.

 ii) Tongue Frontness / Backness: It is concerned with the part of tongue between the front and the back, which is raised high. From this point of view the vowel sounds can be classified as front vowels and back vowels. By changing the shape of the tongue we can produce vowels in which a different part of the tongue is the highest point. That means, a vowel having the back of the tongue as the highest point is a back vowel, whereas the one having the front of the tongue as the highest point is called a front vowel. For example: during the articulation of the vowel / u: / the back of the tongue is raised high, so it’s a back vowel. On the other hand, during the articulation of the vowel / æ / the front of the tongue is raise high, therefore, it’s a front vowel.

(vi) The Jaws: Some phoneticians consider the jaws as articulators, since we move the lower jaw a lot at the time of speaking. But it should be noted that the jaws are not articulators in the same way as the others. The main reason is that they are incapable of making contact with other articulators by themselves.

(vii) The Nose and the Nasal Cavity: The nose and its cavity may also be considered as speech organs. The sounds which are produced with the nose are called nasal sounds. Some nasal sounds in English include: /m/n/ŋ/.