VOWELS IN STANDARD AUSTRIAN GERMAN - Acoustics ...

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Vowels in Standard Austrian German
In this case, only one speaker (sp012) makes no difference between the two positions.
All the other speakers differentiate either one formant (sp129), two formants (sp180), or
all three formants (sp082, sp126, sp127). The direction of the change is in accordance
with the results on intensity presented in Heldner (2003): the vowel of /dis/ directly
preceding the noun shows a higher F1 and a lower F2 and F3. From an articulatory
point of view, the degree of mouth opening and the degree of constriction (tongue-
palate distance) are enlarged, whilst the length of constriction is possibly shortened.
6.6.5 The rhythm of speech
The above examples vividly show that a) relative sentence stress affects the spectral
shape of the vowels and b) the realization of relative sentence stress is highly speaker
dependent. The reason for the existence of such graded differences lies in the inherent
rhythmic behaviour of speech which requires a succession of foregrounding and
backgrounding. Sentence stress finds its expression only in relation to the other entities
in a sentence or an utterance. Therefore, it is strongly connected to the rhythm of speech
or, to put it more explicitly, the relative stress levels assigned to phonemes, syllables,
and words, which make up what is perceived as a rhythmic behaviour in the so-called
stress-timed languages.
Rhythm is generally highly connected with timing; with ideal beat intervals of
about 300 ms to 400 ms (Schreuder 2006: 101). In so-called stress-timed languages,
these intervals are supposed to stay equally long regardless of the amount of unstressed
syllables in between. This assumption has triggered a further, implicit hypothesis,
namely that the degree of reduction imposed on unstressed syllables depends on the
amount of unstressed syllables between two stresses. The isochrony hypothesis was
never confirmed, leading to other – statistical – methods to classify languages (see e.g.
Low & Grabe 1995, Low et al. 2000, Grabe & Low 2002, Ramus et al. 1999, Ramus
2002, Galves et al. 2002, Rouas et al. 2005, see Cummins 2002, Wagner 2002 for a