This work was aimed at analyzing the frequency variations of the lowest main spectral peak in the production of sibilants. According to the quantal theory of speech production, a continuous articulatory movement from /s/ to /f/ (or vice-versa) should provoke an abrupt and discontinuous change in the frequency of this peak. In the present work, a French native speaker was asked to produce consonant clusters of the type [sf] and [fs] combined with [a], [i] and [u]. Articulatory (electromagnetic) data and acoustic data were simultaneously recorded. First results show that variations of the acoustic output as a function of the location of the constriction are clearly non-linear when the surrounding vowels are unrounded. In the vicinity of [u] however, the acoustic transition between the two fricatives are more gradual, probably because [s] is produced in that context with a rounding of the lips which results in a lowering of the spectrum.
Bibliographic reference. Nguyen, Noel / Hoole, Philip (1993): "Frequency variations of the lowest main spectral peak in sibilant clusters", In EUROSPEECH'93, 81-84.