VOWELS IN STANDARD AUSTRIAN GERMAN - Acoustics ...

Sylvia Moosmüller
cm 2 . Then F2 rises another 200 Hz as the constriction area of the lips increases to about
0.5 cm 2 (Manuel & Stevens 1995: 437). In the present example (Figure 5.10), the
calculated F2 of 1040 Hz at constriction area = zero is canceled by a well-developed
antiresonance. Two pronounced spectral peaks emerge in the burst spectrum at
approximately 2280 Hz and 2900 Hz. Taking into account that the example is spoken by
a female speaker, the values measured are in correspondance with the calculations and
measurements of Fant (1970) for the Russian palatalised labials.
"The double peak of F2 + F3 of palatalized labials often shows up in spectrograms as an
apparent central energy concentration, which might make the labial interval resemble that of
palatals. [...] However, the spectrum is distinct from that of palatals owing to the zero just
below F2 and the more prominent low frequency region. The two peaks are generally less
close than in palatals, and their overall energy is lower. In addition there are, of course, the
apparent transitional cues." (Fant 1970: 188)
This means that the tongue is already in the pre-palatal position for /i/ at the time
of release; the delay in formant frequency positioning is caused by the second compo-
nant, the opening of the bilabial occlusion, which takes about 10 ms from the point of
release and manifests itself in the upward movement of F2 and F3.
These few examples vividly show that in an acoustic study on coarticulation, the
activity of the articulators cannot be seen independently from one other. Moreover, what
can be analyzed independently from an articulatory point of view results in one acoustic
output containing two or more components. Thus, articulatory and acoustic observations
of the same speech events may tell different stories. An x-ray motion film can show
what happens during a bilabial occlusion: an inspection of the burst spectrum of a
bilabial plosive reveals the vocal tract configuration at the time of release plus the
change in area of the lip configuration. What exactly happens during the occlusion
(diphthongal movement of the tongue or deactivation of the tongue musculature) cannot
directly be observed in the acoustic output.
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