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Section 3 The Physical Features of English Vowels

Vowel quality How can I figure out the unique qualities of English vowels and consonants that are different from other vowels. How do I know that each vowel of a language may be very different from its counterpart in other languages? What are the basic and useful elements that help us understand the physical features of each sound? What instrument can we use for this purpose? How can the findings help us or our students improve English pronunciation? Authentic samples: Sample 1; sample 2; sample 3.

Finding the qualities of the vowel We start with looking at spectrograms of sounds. We make spectrograms to see how the spectra of speech change in time. In a spectrogram we get a permanent image of spectral changes. A spectrogram is like a visual recording of what we have just heard or of what happened as someone spoke. So we can examine and measure the changing sequence of sounds. To examine the spectra of changing speech we need to be able to look at three variables: time, frequency, and amplitude. See the following examples:

Finding the qualities of the vowel Spectrograms enable us to measure the durations of vowels and the frequencies of their formants. By describing the formant frequencies and how they change time, we can accurately describe the vowel sounds a person produces. Spectrograms show this information and can be used to observe the timing of each event that occurs during speech. Now let’s see how formants look like. How do F1 and F2 help us locate the vowel space of each vowel in English?

The vowel space

Monophthongs or diphthongs? Can you identify the following vowels as monophthongs or diphthongs? [ou] [I]  [u]  [Q]  [au]  [aI] Can you identify the “track” of the sounds mentioned above?

Monophthongs or diphthongs? Can you identify the following vowels as monophthongs or diphthongs? [ou] [I]  [u]  [Q]  [au]  [aI] Can you identify the “track” of the sounds mentioned above?

Compare the “tracks” of the diphthongs

Rounded and unrounded vowels Front vowels are unrounded vowels. How do you read /U/ in “good” “cook” “took” and “book”? What about “food”? Do you pronounce /u/ sound in a rounded way?  What is the difference between the English /u/ sound and the Mandarin /u/ sound. Identify the track of the /ju/ sound in English.

Rhotacization The feature rhotacization describes an auditory property, the r-coloring, of a vowel. In most forms of American English, there are both stressed and unstressed rhotacized vowels. The transcription for the phrase "my sister's bird" in most forms of American English would be [maI 'sIstÔz 'bÎÕùd]. X-ray studies of speech have shown that in both these ways of producing a rhotacized quality there is usually a constriction in the pharynx caused by retraction of the part of the tongue below the epiglottis.

Unstressed syllables The symbol [«] or [®]may be used to designate many vowels that have a reduced vowel quality.

Tense and lax vowels Not simply a matter of “tension” Closed syllables vs. open syllables

Rules for English vowel allophones 1. A given vowel is longest in an open syllable, next longest in a syllable closed by a voiced consonant, and shortest in a syllable closed by a voiceless consonant. 2. Other things being equal, vowels are longer in stressed syllables. 3. Other things being equal, vowels are longest in monosyllabic words, next longest in words with two syllables, and shortest in words with more than two syllables. speed speedy speedily

"4" 4. A reduced vowel may be voiceless when it occurs after a voiceless stop (and before a voiceless stop). permission, tomato, compare, potato, catastrophe preparatory, introduction, replicate, complicate 5. Vowels are nasalized in syllables closed by a nasal consonant. ban, run, seen 6. Vowels are retracted before syllable final [É]. peel, pail, pal