SPEECH ARTICULATION: Vowels David Brett David Brett

Vowels may differ in three ways Length Quality (i.e. the difference between /i:/ and /u:/ Oral or nasal production (unlike French, this does not have a phonemic function in English)

We will now look at how vowels vary in quality…

These are x-rays of a person producing different vowels

In the close front position (unrounded) we produce /i/

In the open front position (unrounded) we produce /a/

Back open (unrounded) : /  /

Back close (rounded): /u/

Connecting these points gives us a box called the Vowel Quadrilateral

All the vowel sounds that the human voice can produce may be plotted within the limits of the quadrilateral

While the quadrilateral system is widely used it remains a hypothesis and is not necessarily the only possible way of representing vowels

Here is the vowel quadrilateral divided into sectors with the IPA symbols at fixed points. These are called Cardinal Vowels.

This is the full set:

N.B. Do not confuse symbols for cardinal vowels with language specific phonemes The IPA vowel quadrilateral is a grid on which we can plot vowels It indicates the total area in which vowels can be produced by human beings, the cardinal vowels are fixed reference points on this chart, just like lines of longtitude and latitude on a map Plots of language specific vowels do not usually correspond to the cardinal vowels, e.g. the Italian /a/ does not correspond to the cardinal vowel [a]

The vowels appear in pairs depending on whether they are articulated with spread lips, (unrounded ) indicated here in green:

Or with rounded lips (red):

Generally, front vowels are unrounded and back vowels rounded…

Italian and English follow this pattern…

…while German and French do not (v. /y/, /  / etc.)

These are the places of articulation of English short and long vowels

The vowel system of Br English ShortLong /ɪ//ɪ/ Fish/i:/Week /e/Bed / ɔ :/ Door /æ/Cat / ɑ :/ Car /ʌ//ʌ/ Cut/u:/Food /ə/Mother / ɜ :/ Nurse /ʊ//ʊ/ Good /ɒ//ɒ/ Dog

The chart of Standard Italian vowels would look like this:

The fact that Italian lacks vowels in the central area may well explain why Italian students of English have so much trouble with these sounds

However, it is important to remember that the cardinal vowel system describes vowels from an articulatory point of view…

…whereas vowels are an acoustic phenomenon and may also be described according to their acoustic properties.

Spectrogram of four vowels: /i:/, /  /, /  :/ and /u:/

Each vowel has a different disposition of formants (peaks at certain frequencies)

Plotting the values of the 1 st and 2 nd formants results in a graph which greatly resembles the quadrilateral

We can note that the values of the acoustic properties are not always exactly the same: they tend to vary considerably

This type of analysis can be used to illustrate the difference between native (left) and non-native speakers’ production (right)

Native (left) and non-native speakers’ production (right)

Any questions?