How Vowel Sounds are Produced

Speech sounds of English are 44 sounds. These sounds can be divided into two groups: Consonants (24) and vowels (20). The consonants are also divided into two categories: voiceless and voiced sounds. The voiceless are nine: k, p, t, f, h, s, ɵ, tʃ, and ʃ. The voiced are fifteen: b, d, g, w*, j*, n, m, Å‹, z, dÊ’, Ê’, °, l, r, and v.

The action of the vocal cords (i.e., the state of the glottis) determines weather a sound being produced is voiced or voiceless. When the vocal cords are brought close together, but not shut tightly, the air escaping from the lungs causes them to vibrate: this is called voicing, and a sound produced while the vocal cords are vibrating is a voiced sound. When the vocal cords are apart, no vibration occurs, and sounds produced with the glottis in this state are voiceless sounds.

Are /j/ and /w/ consonant or vowel sounds?

The two semi- vowels /j/ and /w/ are mainly vocalic glides that start near a close vowel, /i/ or /u/. The most important thing to remember about these phonemes is that they are phonetically like vowels but phonologically like consonants. These sounds resemble vowels in their open articulation and in being voiced, but differ from them in other phonetic aspects; in other words, they display consonantal behavior in relation to other sounds. The definite article the, for example, is pronounced / °É™/ before /j, w/, as in / °É™ jiÉ™/, /°É™ we°É™ /, the year, the weather respectively, in which case the semi-vowels appear to behave like consonants. By the same token in RP the /r/ usually deletes before the semi-vowels as it does before consonants so the sequences for women, for you are realized as / fÉ™ ju:, fÉ™ wumÉ™n /respectively.

What is meant by a vowel?

A vowel is defined as a sound which is produced or made without any kind of obstruction (closure or impediment) to the flow of air in the mouth as it passes from the larynx to the lips. In all vowels, the mouth passage is unobstructed. If it is obstructed at any time during the production of a speech-sound, the resulting sound will be a consonant. So the difference between vowels and consonants is a difference in the way by which they are produced. In other words, vowels are the sounds which are produced without narrowing or closure of the air passage. Vowel sounds, of course, normally voiced, so that the voicing is not relevant for their production.

There are three parameters by which we describe a vowel in English: first the height of the tongue or openness of the mouth. This gives us the categories: close, half-close, half-open, open (an alternative set of categories is also sometimes used: high, mid-high, mid-low, low). Second, the area of the mouth that has the highest part of the tongue or the general area of the mouth in which the vowel is made. This gives us the categories: front, central and back. A third set of categories involves the shape of the lips; the categories are roundeded and spread (unrounded).

Vowels of English can be divided into two categories: pure vowels and diphthongs. The pure vowels are 12 sounds and the diphthongs are 8 sounds.

The difference between pure vowels and diphthongs (glides):

The pure vowels are the ones that are made with the mouth taking up a single position during the articulation. Diphthongs, by contrast, are vocalic glides, and the configuration of the mouth changes in the course of the articulation of the vowel sound. . In other words, diphthongs are the sounds that consist of a movement or glide from one vowel to another. A vowel which remains constant and does not glide is called a pure vowel. Unlike the pure vowels, diphthongs are defined as vowel glides produced by a quick movement of the tongue from one position to another. The vowel in hat, for example, is produced differently from that in hate -the former is realized with a pure vowel /æ/; the latter with a diphthong /eı/. Note the change in the vowel quality in the realization of /eı/ where the tongue glides quickly from the position of /e/ to that of /i/.

Features of vowels

[+syllabic], [-consonantal], [+continuant], [+voiced], [-sibilant], [+sonorant]

Pure vowels: (12)

Pure vowels of English can be classified into three groups according to the general area of the mouth in which they are made or produced. There are three areas in which pure vowels are produced: Front, Central and Back.

Front vowels (4) /i: /, /I/, /e/, /æ/

In the front area of the mouth (tongue), English has four vowels. These four front vowels are made with spread (unrounded) lips. Two vowels are in the close area. One is the close front spread vowel found in beat or sheep and symbolized by /i:/ , so these words can be described phonetically as /bi:t/ and / ʃi:p/.It also occurs initially as in eat /i:t/ and finally as in tea /ti:/. The other is a more open and a more central close front vowel, usually described as a lowered and centralized close front spread vowel. It is represented by the symbol /I/, and it occurs initially as in in /in/, medially as in sit /sit/ and finally as in happy /hæpi/.

English has no a vowel at precisely either the half-close or the half-open position, but one mid way between the two. This is usually described as mid front spread vowel. It is sometimes symbolized by e (É›). This vowel occurs initially as in egg /eg/, medially as in set /set/, and it does not occur finally. The other English front vowel is in the open area but it is not completely open: it is somewhere between half-open and open, although it is usually as an open front spread vowel. This front vowel can occur initially as in and or an /ænd, æn/, medially as in man, can, /mæn , kæn/ and finally this vowel does not occur.

Back vowels (5) /a: /, /É”/, /É”: /, /u/, /u: /

In the back area of the mouth we can recognize five vowels in English. Four of them are made with rounded lips and one with spread lips. There are also two vowels in English that fall in the close back area. One is the close back rounded vowel, as found in boot and tool and symbolized by u:, so these words will be transcribed phonetically as /bu:t/ and /tu:l/. The other is a more open and more central variety. It usually described as a (lowered and centralized) close back rounded vowel. It is represented by the symbol u. It occurs medially as in put and book.

As in the case of front vowels, English has no vowels at precisely half-close and half-open back position. There is one vowel somewhere between the two, probably nearer to half-open than half-close. It is symbolized by É”: It may be described as a mid back rounded vowel. It occurs initially as in orbit, order, medially as in ball, and bought.

In the open back area two vowels are found in English, one made with rounded lips, the other with spread lips. The open back rounded vowel is, is like its front counterpart, not completely open but somewhere between half-open and open. It is symbolized by É”. It may be described as an open back rounded vowel. It occurs initially as in of, on, odd, and medially as in dog, top, and dot.

The open back spread vowel is not completely back and it tends towards the central position. This vowel is symbolized by a:. It occurs initially as in arm, medially as in part and finally car.

Central vowels: /ʌ/, /3:/, /ə/

We come now to the final group of pure vowels, those made in the central area of the mouth. There are three vowels produced in this area in English, all with spread lips. One of these vowels is in the open area, but like a and ɔ in fact mid-way between half-open and open, although it is described as an open central spread vowel. It is represented by the IPA symbol for a half-open back spread vowel, namely ʌ. This vowel occurs initially as in up, under, and medially as in but/ /bʌt/ and some /sʌm/.

The other two central vowels in English are both mid central spread vowels, that is mid-way between half-close and half-open. One is represented by the symbol 3:. It occurs initially as in earth and earn, and medially as in girl bird, etc. The latter sound is often referred to the schwa vowel. It is symbolized by É™ and it can be described as an unstressed mid central spread vowel. It occurs initially as in above /É™bÊŒv/, along /É™lɔŋ /, ahead /É™hed/, medially as in consider / kÉ™nsIdÉ™/, consist /kÉ™sIst/, continue/ kÉ™ntInju:/ and finally as in father/ fa:°É™/, teacher/ ti::tʃə/.

Diphthongs (8)

As mentioned above diphthongs are the sounds that consist of a movement or glide from one vowel to another. Unlike the pure vowels, diphthongs are defined as vowel glides produced by a quick movement of the tongue from one position to another. In other words, they are a combination of two vowels. They are eight vowels: /ai/, /ei/, /ɔi, /au/, /əu/, /eə/, /iə/, /uə/. The easiest way to remember them is in term of three groups divided as in the below diagram

The closing diphthongs have the characteristic that they all end with a glide towards a closer vowel I or u.

The first closing diphthong is /ei/. The beginning point of this diphthong is the mid front spread pure vowel of English e. It occurs initially as in aim, age ate, medially as in lake, take, make and finally as in say, and play.

A second diphthong in this group begins with an open front spread vowel a, moving towards the closing front spread vowel i . This diphthong is represented by ai. This vowel occurs initially as in aisle, medially as in nine, and finally as in buy.

The third diphthong in this group begins with a mid (between open and half-open) back rounded pure vowel ɔ, moving towards the close front spread vowel i. This diphthong is represented by ɔi. It occurs initially as in oil, medially as boys and finally as in joy.

The second group of diphthongs comprises those tending u. The first in this group starts with the unstressed mid central spread vowel É™ moving towards u.

This diphthong is symbolized with əu. It occurs initially as open, medially as in home and finally as in go.

The other in this group starts with an open central spread vowel a, moving towards u. It is represented by au. It occurs initially as in out, medially as in house and finally as in now.

The third group is the centering diphthongs glide towards the É™ (schwa) vowel. In other words, the diphthongs of this group tend towards the mid central spread vowel É™.

First, the diphthong that begins with (the lowered centralized) close front spread vowel I, moving towards the vowel É™. This diphthong is represented by iÉ™. It occurs initially as in ears, medially as in museum and finally as in clear, fear and here.

The second diphthong in this group begins with a mid front spread vowel e, moving towards É™. It is represented by eÉ™. It occurs initially as in airline, medially as in shares and finally as care, fair, pair and hair.

The last diphthong in this group begins with the close back rounded vowel u, moving towards the unstressed central spread vowel É™. It is symbolized by uÉ™. This diphthong occurs medially as in cruel, and finally as in pure, poor, and sure.

Summary

Features of English vowels

uː  

ÊŠ

É”

ɔː

ɑː 

ʌ

æ

ɜː  

e

iː

ı

+

+

+

+

+

+

+

+

+

+

+

Syllabic

_

_

_

_

_

_

_

_

_

_

_

Consonantal

+

+

+

+

+

+

+

+

+

+

+

Sonorant

+

+

_

_

_

_

_

_

_

+

+

High

_

_

_

+

_

_

+

_

_

_

_

Low

+

+

+

+

+

_

_

_

_

_

_

Back

+

+

+

+

_

_

_

_

_

_

_

Round

+

+

+

+

+

+

+

+

+

+

+

continuant

_

_

_

_

_

_

_

_

_

_

_

Sibilant

Pure vowels

iː   a close, front, spread vowel

ı a (lowered and centralized) close, front spread vowel.

e      a mid, front, spread vowel

æ an open, front, spread vowel

uː    a close, back, rounded vowel

ÊŠ a (lowered and centralized) close, back, rounded vowel

:ɔː  a mid (between half-close and half-open) back, rounded vowel

É” a mid (between open and half-open) open, back, rounded vowel

ɑː  an open, back, spread vowel

:ɜː  a mid, central, spread vowel.

ʌ an pen, central, spread vowel

É™ an unstressed, mid, central, spread vowel

Diphthongs

eı begins with the mid (between half-close and half-open) front spread vowel e, moving towards (lowered and centralized) close front spread vowel ı.

aı begins with the open front spread vowel a, moving towards the (lowered and centralized ) close front spread vowel ı.

ɔı begins with the mid (between open and half-open) back rounded pure vowel ɔ, moving towards the close front spread vowel i

əu begins with the unstressed mid central spread vowel ə moving towards (lowered and centralized ) close front spread vowel u.

au begins with the open central spread vowel a, moving towards the (lowered and centralized ) close back rounded vowel u.

eÉ™ begins with the mid front spread vowel e, moving towards the unstressed mid central spread vowel É™.

iÉ™ begins with the (lowered centralized) close front spread vowel i , moving towards the vowel the unstressed mid central spread vowel É™.

uÉ™ begins with the close back rounded vowel u, moving towards the unstressed central spread vowel É™.