  A state-of-the-art 1D acoustic synthesizer has been previously developed, and
coupled to speaker-specific biomechanical models of oropharynx in ArtiSynth. As
expected, the formant frequencies of the synthesized vowel sounds were shown to
be different from those of the recorded audio. Such discrepancy was
hypothesized to be due to the simplified geometry of the vocal tract model as
well as the one dimensional implementation of Navier-Stokes equations. In this
paper, we calculate Helmholtz resonances of our vocal tract geometries using 3D
finite element method (FEM), and compare them with the formant frequencies
obtained from the 1D method and audio. We hope such comparison helps with
clarifying the limitations of our current models and/or speech synthesizer.
