VOWELS IN STANDARD AUSTRIAN GERMAN - Acoustics ...

Sylvia Moosmüller
It becomes apparent from Figure 6.10 that, for almost every vowel category, F2 plays
the dominant role in differentiating stressed from unstressed vowels. A salient exception
is the vowel /A/, which discriminates stressed from unstressed vowels predominantly via
F1 (i.e. the degree of lip opening is smaller for the unstressed /A/s). It is worth
mentioning that for the [–constricted] vowels /E/ and /O/ – for those speakers where
statistically significant differences appear 135 – F1 is lowered in the unstressed position
as well (i.e. the degree of lip opening decreases in unstressed position). For the other
vowels where statistically significant differences appear, F1 becomes higher in the
unstressed position. These results suggest that F1 varies less in unstressed positions as
compared to stressed positions. The calculation of the variability coefficient over all
stressed and unstressed vowels corroborates this assumption: the variability of F1 of the
stressed vowels is higher than the variability of the unstressed vowels (p < 0.01) 136 .
Figure 6.11 shows the results of the calculated variability coefficient over all vowels for
F1 in spontaneous speech:
135 In the sentence reading task, all speakers exhibited a statistically significant difference of
F1 of the vowels /E/ and /O/. In spontaneous speech, statistically significant differences
could only be observed for the speakers sp126, sp127, sp082, and sp180 for the vowel /E/,
and the speakers sp082 and sp180 for the vowel /O/.
136 One-tailed t-tests have been performed.
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