VOWELS IN STANDARD AUSTRIAN GERMAN - Acoustics ...

Variability coefficient
40,000
35,000
30,000
25,000
20,000
15,000
10,000
5,000
0,000
207
Vowels in Standard Austrian German
sp012 sp126 sp127 sp082 sp129 sp180 all
stressed 22,002 22,042 29,904 22,349 24,723 36,383 26,234
unstressed 16,923 14,199 15,310 17,565 15,176 23,466 17,106
Figure 6.11: Variability coefficient of F1 calculated over all vowels in stressed and unstressed
position, broken for speakers, spontaneous speech. Legend: sp = speaker.
The results for the sentence reading task do not differ from spontaneous speech. The
calculated variability coefficient is about the same: 28.24 in stressed position and 16.47
in unstressed position (pooled over all speakers). Consequently, no statistically
significant differences appear between the two speaking tasks, either in stressed, or in
unstressed position.
F2, in a case where statistically significant difference occurs between stressed and
unstressed vowels, is lowered for the front vowels and raised for the back vowels, due
to a reduction of constriction degree, constriction length and lip protrusion (for the back
rounded vowels). The changes involved with respect to F2 lead to a substantial and
statistically significant (p < 0.01) reduction of the variability of unstressed vowels.
Figure 6.12 gives the variability coefficient calculated over all vowels in stressed and
unstressed positions in spontaneous speech.