2. The method as recited in claim 1 , wherein the first and second representations of the phoneme are computer generated by: synthesizing a glottal source for the phoneme; filtering the synthesized glottal source with formant resonators to produce the first representation of the phoneme; and processing the synthesized glottal source with a time-varying filter to produce the second, relatively more spectrally complete representation of the phoneme, wherein the time-varying filter substantially matches the spectro-temporal properties of a natural production of the phoneme, and wherein the second representation of the phoneme at least partially replicates natural production of the phoneme.
4. The method as recited in claim 2 , wherein a blended representation of the phoneme is generated by: multiplying waveforms of the first representation of the phoneme and the second representation of the phoneme by respective coefficients to generate a weighted simplified phoneme waveform and a weighted complex waveform; and adding the weighted simplified phoneme waveform and the weighted complex phoneme waveform to generate the blended representation.