Unit 4:

Vowel Sounds

Vowel sounds are produced in most cases without any kind of contact between the articulators. They can be made different from each other mainly by raising a certain part of the tongue to different levels, by modifying the shape of the lips and by raising and lowering the velum. Variations of this kind produced by changing the shape of the mouth resonator are referred to as differences in vowel quality.

X-ray photographs of tongue positions for different vowels show, on the one hand, that the part of the tongue raised may be any point between the front and the back. They also show that the highest part of the tongue always occupies points within an oval-shaped area called the vowel area. For purposes of classification, it is convenient to describe. the raising of three basic parts of the tongue - front, centre (mid position between front and back), and back.

The vowel sounds of English and Spanish have two characteristics in common. In the first place, they are normally voiced sounds, i.e. they are produced with vibration of the vocal folds; in the second place, they are usually oral sounds, i.e. when the vibrating column of air reaches the top of the pharynx it generally escapes through the mouth only. Occasionally there are devoiced and nasalized vowel sounds in English and Spanish, but this is not a common characteristic.

The Cardinal Vowels

In 1917 Daniel Jones took the vowel area as the basis for establishing a vowel diagram and devised a system of Cardinal Vowels (CVs), which are still widely used in phonetic research today, For practical reasons the vowel diagram used nowadays is the result of a series of modifications of the original vowel area.

The system is based on two articulatorily selected vowel sounds. The first is produced by raising the tongue as close as possible to the palate without causing friction. The result is the sound [i], which is called Cardinal Vowel No. 1 (CV 1).

The second is produced by placing the tongue as low and as far back as possible. The result is the sound [a], which is called CV 5. It is possible to produce sounds between these two points. CVs 2, 3 and 4 [e, ɜː, a] respectively, are produced at auditorily equidistant points between [i] and [ɒ] by gradually lowering the front of the tongue. CVs 6, 7 and 8 [ɔː, o, u] respectively, are produced at auditorily equidistant points between (a] and [i] by gradually raising the back of the tongue.

The result is a system of eight Cardinal Vowels, which do not belong to any particular language, but which can be used as reference points. The vowel sounds of any language can be identified by comparing them with this system. The advantage of using Cardinal Vowels is that their quality is invariable and permits accurate comparison. The only way to learn to pronounce them is by oral instruction.

The Cardinal Vowels are on the limits of the vowel diagram, i.e. they occupy peripheral, extreme positions. If the tongue exceeds this limit, friction will be heard. CVs 1, 2, 3, 4, and 5 are pronounced with spread or open lips, and the last three with lip rounding

VOWEL SOUNDS

Source: English File. Oxford University Press

https://elt.oup.com/student/englishfile/advanced3/pronunciation?cc=global&selLanguage=en#practice

Classification of vowel sounds

Fig 9 shows the classification labels for the articulation of vowel sounds. The labels, corresponding to tongue positions, may be placed on two axes - a horizontal one indicating 'part of t h é tongue which is raised, and a vertical one indicating height to which the tongue is raised. For example, the vowel sound

[e] in Eng. set is articulatorily classified as 'mid front', because the front of the tongue rises to the mid position; [u] as in Eng. boot is classified as 'close back', because the back of the tongue rises to the close position, and [3], as in Eng. Bert, as 'mid central', because the central part of the tongue rises to the mid position. Vowels occupying intermediate positions between front and central are retracted (e.g. the vowel sounds [ɪ ] in Eng. pity ); those between central and back are advanced (e.g. [ʊ] in Eng. look).

For a more complete classification, a final articulatory feature may be added, lip position. In the case of English and Spanish two general labels are enough: rounded and unrounded in various degrees. Front vowel sounds in these two languages are unrounded; back ones are rounded, except the one in Eng. arm.

Vowel quality can also be described in auditory terms, with reference to the Cardinal Vowels. For example, the vowel sound in Sp. sí is near CV 1 , and the one in Sp. tú near CV 8.

A final classification of vowel sounds states whether their quality is relatively sustained (i.e. the tongue remains in a more or less steady position), or whether there is a considerable glide from one vowel sound to another within the same syllable. In the first case, we refer to pure (or relatively pure) vowel sounds; in the second to diphthongs. These can be shown on the diagram with beams which go from the first element (starting point) in the direction of the second element.

The Primary Cardinal Vowel

Book: Carr, P. (2013). English Phonetics and Phonology. An Introduction. Second Edition. London: Wiley-Blackwell.

Let us begin by assuming that all vowels are voiced and are articulated with a constriction of open approximation. We will also assume, for the moment, that all vowels are oral sounds

(i.e. that the velum is raised during their production). The range of positions which the tongue can occupy within the oral cavity while remaining in a constriction of open approximation is quite large. Let us call the entire available space for such articulations the vowel space. We will require a means of plotting the point at which a given vowel is articulated in the vowel space. In order to do this, we will appeal to an idealized chart of that space, as follows (this chart is repeated in the IPA chart in figure 2):

(1) The vowel space and the primary cardinal vowels

In this diagram, we represent the vowel space along two dimensions. The first is the high/low dimension (also referred to as the close/open dimension), depicting the height of the body of the tongue during the articulation of a vowel (i.e. depicting vowel height). This is represented as the vertical axis in the diagram. The second is the front/back dimension, depicting the extent to which the body of the tongue lies towards the front of the vowel space. This is represented as the horizontal axis in the diagram. We may identify three arbitrary points along this dimension: front, central and back.

In using these two dimensions, we can say, for any given vowel, how high in the vowel space it is articulated, and whether it is a front, central or back vowel. To these two descriptive parameters, we will add a third, which refers to lip position: we will say, for a given vowel, whether, during its articulation, the lips are rounded or not. We will refer to the former sort of vowel as a rounded vowel and the latter as an unrounded vowel.

It is convenient to identify several points along the perimeter of the vowel space. Once we have done this, we can plot the location of any given vowel in relation to those points. Vowelsarticulated at those points are called the cardinal vowels. We will now identify eight of them.