Further to the postings about secondary cardinal 19 (reverse E) on PHONET
a few weeks ago, I post below some data on formant frequencies based on my
own speech.
In the original PHONET postings, John Wells mentioned a close-mid
realisation of schwa in RP. The formant measurements below were made in
response to a query on the HISTLING list (HISTLING. Historical
Linguistics. Server: [log in to unmask] Questions:
Dorothy Disterheft, [log in to unmask]) about schwa raising
in British English, which originally suggested that schwa in the
words 'Saddam' and 'communicate' was close mid. The quality of the vowels
in these two words is non-identical in my British English speech, and so I
undertook some measurements of my own speech to put matters on a more
objective footing. The word 'communicate' could not be used for comparison
due to nasalisation, and as I felt that coronals had an effect of raising
schwa in this way, the word chosen for comparison of schwa in non coronal
context was 'Copernicus'. The word 'Sidney' was also measured to provide a
comparison with /I/, which had been identified in the HISTLING postings
as the result of schwa raising.
Formant measurements were made of single FFT and LPC spectra at the vowel
midpoint (128 sample window at 11025 sample rate). The words used
were 'Saddam' with coronal consonants either side of the unstressed
schwa, 'Copernicus' with non-coronal consonants flanking the unstressed
schwa, and 'Sidney, with coronals flanking a stressed /I/ for comparison.
Three tokens each recorded in a carrier sentence "Say X again" by me - 31
yr old male speakers of Southern British English. The unstressed vowel
of 'Saddam' had an average duration of 49.3 ms (range 47-53 ms) and
of 'Copernicus' had an average duration of 31.3 ms (range 28-36 ms). The
stressed vowel of 'Sidney' had an average duration of 56.7 ms (range 49-69
ms).
F1 values for 'Saddam' ranged between 330 Hz and 400 Hz (average 373.3 Hz)
whereas F1 for 'Copernicus' showed values between 435 Hz and 460 Hz
(average 446 Hz) - F1 was therefore lower for the 'Saddam' vowel.
For 'Sidney', F1 was 384 Hz on average (range 360-408 Hz).
F2 values were average of 1601 Hz for 'Saddam' (1541-1641 Hz range) and
1621.3 Hz for 'Copernicus' (range 1600 - 1643 Hz). F2 was therefore also
lower on average, though the range for 'Saddam' was greater, and F2 was
moving in the case of 'Copernicus'. The fall in F2 throughout the vowel
in 'Copernicus' was 394.7 Hz on average (range 172 - 603, Hz values at
onset and offset between 1809 and 1206 respectively). For 'Sidney', F2
moved little and was 1865.7 Hz on average (range 1813-1910 Hz).
F3 values were more or less static throughout. The average for 'Saddam' is
2577.7 Hz (range 2541 - 2571), and for 'Copernicus' 2400.3 Hz (range 2400 -
2401). F3 was therefore higher for the 'Saddam' vowel. In 'Sidney', F3
was also static and at 2546 Hz on average (range 2498-2594 Hz).
In short, the schwa of 'Saddam' can be plotted as being closer and further
forward in the F1-F2 vowel space than schwa of 'Copernicus', and a close
mid description is appropriate. It is not as front as /I/. F3 values also
differ, with greater similarity seen between /I/ and the (if I may label
it as such) 'Saddam' vowel.
Although these data are only for one speaker, they demonstrate that schwa
raising is probably a phonetic effect due to surrounding coronals. The
consonantal effect is probably greater than we would see with a stressed
vowel due to the brief duration of the schwa, although there may be other
phonological issues here too. The effect on schwa is considered to be a
combination of coarticulatory lingual posture and a high jaw position for
the surrounding coronals. Auditory consideration of my own speech suggests
that onset /l/ does not have this effect, and the jaw position for /l/ is
in my speech lower than that for /t, d, s, z/ or /n/. As these sounds are
all coronal, it seems that jaw position may be the major factor in the
vowel quality effect.
Finally, Mees and Collins, in their chapter on Cardiff English in the book
Urban Voices (Paul Foulkes and Gerard Docherty, Arnold, 1999: 189),
mention that the Cardiff realisation of the RP STRUT vowel tends to be
schwa, and that close mid realisations are very common. They do not
mention variation due to any particular environments.
Mark Jones
Department of Linguistics
University of Cambridge
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