Secondary narrowings in the vocal tract

Pharyngealized vowels occur in some languages; Sedang uses this contrast, as do the Tungusic languages. Pharyngealisation is similar in articulation to retracted tongue root, but is acoustically distinct.

A stronger degree of pharyngealisation occurs in the Northeast Caucasian languages and the Khoisan languages. These might be called epiglottalized, since the primary constriction is at the tip of the epiglottis.

The greatest degree of pharyngealisation is found in the strident vowels of the Khoisan languages, where the larynx is raised, and the pharynx constricted, so that either the epiglottis or the arytenoid cartilages vibrate instead of the vocal cords.

Note that the terms pharyngealized, epiglottalized, strident, and sphincteric are sometimes used interchangeably.

Rhotic vowels

Main article: R-colored vowel

Rhotic vowels are the "R-colored vowels" of English and a few other languages.

Tenseness/checked vowels vs. free vowels

Tenseness is used to describe the opposition of tense vowels as in leap, suit vs. lax vowels as in lip, soot. This opposition has traditionally been thought to be a result of greater muscular tension, though phonetic experiments have repeatedly failed to show this.

Unlike the other features of vowel quality, tenseness is only applicable to the few languages that have this opposition (mainly Germanic languages, e.g. English), whereas the vowels of the other languages (e.g. Spanish) cannot be described with respect to tenseness in any meaningful way. In discourse about the English language, "tense and lax" are often used interchangeably with "long and short", respectively, because the features are concomitant in the common varieties of English. This cannot be applied to all English dialects or other languages.

In most Germanic languages, lax vowels can only occur in closed syllables. Therefore, they are also known as checked vowels, whereas the tense vowels are called free vowels since they can occur in any kind of syllable.

Acoustics

Spectrogram of vowels [i, u, ɑ]. [ɑ] is a low vowel, so its F1 value is higher than that of [i] and [u], which are high vowels. [i] is a front vowel, so its F2 is substantially higher than that of [u] and [ɑ], which are back vowels.

The acoustics of vowels are fairly well understood. The different vowel qualities are realized in acoustic analyses of vowels by the relative values of the formants, acoustic resonances of the vocal tract which show up as dark bands on a spectrogram. The vocal tract acts as a resonant cavity, and the position of the jaw, lips, and tongue affect the parameters of the resonant cavity, resulting in different formant values. The acoustics of vowels can be visualized using spectrograms, which display the acoustic energy at each frequency, and how this changes with time.

The first formant, abbreviated "F1", corresponds to vowel openness (vowel height). Open vowels have high F1 frequencies while close vowels have low F1 frequencies, as can be seen at right: The [i] and [u] have similar low first formants, whereas [ɑ] has a higher formant.

The second formant, F2, corresponds to vowel frontness. Back vowels have low F2 frequencies while front vowels have high F2 frequencies. This is very clear at right, where the front vowel [i] has a much higher F2 frequency than the other two vowels. However, in open vowels the high F1 frequency forces a rise in the F2 frequency as well, so an alternative measure of frontness is the difference between the first and second formants. For this reason, some people prefer to plot as F1 vs. F2 – F1. (This dimension is usually called 'backness' rather than 'frontness', but the term 'backness' can be counterintuitive when discussing formants.)

In the third edition of his textbook, Peter Ladefoged recommended use of plots of F1 against F2 – F1 to represent vowel quality.[4] However, in the fourth edition, he changed to adopt a simple plot of F1 against F2,[5] and this simple plot of F1 against F2 was maintained for the fifth (and final) edition of the book.[6] Katrina Hayward compares the two types of plots and concludes that plotting of F1 against F2 – F1 "is not very satisfactory because of its effect on the placing of the central vowels",[7] so she also recommends use of a simple plot of F1 against F2. In fact, this kind of plot of F1 against F2 has been used by analysts to show the quality of the vowels in a wide range of languages, including RP British English,[8][9] the Queen's English,[10] American English,[11] Singapore English,[12] Brunei English,[13] North Frisian,[14] Turkish Kabardian,[15] and various indigenous Australian languages.[16]

R-colored vowels are characterized by lowered F3 values.

Rounding is generally realized by a complex relationship between F2 and F3 that tends to reinforce vowel backness. One effect of this is that back vowels are most commonly rounded while front vowels are most commonly unrounded; another is that rounded vowels tend to plot to the right of unrounded vowels in vowel charts. That is, there is a reason for plotting vowel pairs the way they are.

A common mistake is to transcribe full vowels for English unstressed syllables. If you transcribe banana as [bænænæ], you are claiming that all three vowels are identical (except in loudness). Even in the slowest and most careful pronunciations, this isn't true. What symbol should be used instead?

The short, sort of accurate, answer is: all unstressed syllables in English have the "schwa" []. The exceptions are that final unstressed syllables can sometimes have full vowels (e.g., potato) and [i] can often be unstressed even in the middle of words (e.g., radiate).

The longer, more accurate answer relies on the distinction between narrow and broad transcription.

Unstressed vowels in English are quite variable. The same speaker will pronounce the vowel [] in the second syllable of enough much the same way every time, but the schwa in the first syllable can be pronounced very differently on different occasions, sometimes even resembling full vowels like [], [], or [].

But if we are interested in a broad transcription, we will ignore them: we will only want to record those differences in sound which can affect the meaning of a word, and in English none of the variation in the first syllable will cause enough to mean something else. So for a broad transcription we use a single cover symbol for all the variations of the unstressed vowel, namely [].

Schwa and R

In broad transcriptions, Rogers transcribes the "er" sound of words like fur/fir as [], even when this occurs in a stressed syllable. This choice has the initial advantage for many learners that all you have to do is turn the more familiar "er" upside down. It has the disadvantage that it's not an accurate reflection of what the mouth is doing. The consonant [] is made by curling the tongue tip upward. In a word like fur, the tongue tip is already curled up by the end of the [f], usually earlier. There is simply no slice of time between the [f] and the [] that we can call a vowel.

One common solution to this problem is to transcribe the "er" sound with the special IPA symbol []. Unfortunately, there are no special symbols to solve the similar problem with [n], [l], and [m] -- for example, in normal speech there is simply no vowel between the [t] and the [n] of button, despite the usual broad transcription . We will return to this problem later in the course when we discuss "syllabicity". For now, it's easiest to continue using schwas in broad transcriptions of words like these.

A dialect glitch

Many speakers of English have intuitions that there are two different unstressed vowels and changing one for the other can change the meaning of the word.

The classical minimal pair to illustrate this distinction, in dialects that make it, is roses versus Rosa's. You could record a speaker of such a dialect saying roses and Rosa's a hundred times each and plot on a graph the position of the speaker's tongue during the final vowel. There would be a large cloud of different positions for roses and a large cloud of positions for Rosa's -- there would be a large area where the two clouds overlapped, but it would still be clear the clouds had different centres.

If you did the same graph for a speaker of a dialect that doesn't make this distinction (like me), the two clouds would overlap so much that there would be no justification for saying that the two words had different vowels.

In transcribing roses and Rosa's, the difference between narrow and broad transcription is again relevant.

For a narrow transcription of a particular utterance, you would record the unstressed vowel as accurately as possible. If utterance 27 of roses was the same as utterance 83 of Rosa's, the two would be transcribed the same way.

For a broad transcription, you would pay more attention to the central positions of the two clouds, which suggest how the two words are generally pronounced.

For dialects which do not contrast the words, where there is really only one cloud, the same symbol would be used for both words: [ozz].

For dialects which do contrast the two words, where the clouds overlap but have different centres, you would use two different symbols; the usual choices are schwa and barred-i, []: Rosa's [ozz] and roses [ozz].

The transcriptions in the textbook fall somewhere in between. Rogers generally uses schwa for the vowels of unstressed syllables, but occasionally uses [] in words where dialects which make the schwa/barred-i constrast would use barred-i, e.g., relax. (This is not entirely consistent. Even if a speaker does have two clouds for their unstressed vowels, the grounds for identifying the higher cloud with the vowel of hit are no stronger than the grounds for identifying the lower cloud with the vowel of cup.)

In my transcriptions, I will only use [] for neutral unstressed vowels, i.e., for all unstressed vowels that are not full vowels, like the [i] in happy or [o] in potato. On assignments and tests, using schwa in broad transcriptions will always be acceptable. It's also a good habit to get into, as one way of unlearning habits that might carry over from English spelling.

In linguistics, specifically phonetics and phonology, schwa (also spelled shwa) can mean the following:

An unstressed and toneless neutral vowel sound in any language, often but not necessarily a mid-central vowel. Such vowels are often transcribed with the symbol <ə>, regardless of their actual phonetic value.

The mid-central vowel sound (rounded or unrounded) in the middle of the vowel chart, stressed or unstressed. In IPA phonetic transcription, it is written as the phone [ə]. In this case the term mid-central vowel may be used instead of schwa to avoid ambiguity.

The Latin letter ə and the Cyrillic letter ә.

Vowel reduction is the term in phonetics that refers to various changes in the acoustic quality of vowels, which are related to changes in stress, sonority, duration, loudness, articulation, or position in the word (e.g. for Creek language[1]), and which are perceived as "weakening".

In phonology, vowel reduction refers to a reduction of the number of distinct vowels, rather than their quality, either over time or when comparing related dialects. In some cases these two concepts may be related. For example, when vowels are phonetically reduced in English, there is also a reduction in the number of vowel contrasts. In other cases, however, phonemic reduction is due to historical vowel mergers (such as the merger of the a vowels in Mary, merry, marry in much of the United States) and has nothing to do with "weakening".

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