All we need is real oscilator sync and the ability to offset the oscillator (sync master) and amplitude modulation
All of which is currently not possible in zebra 2 (except a.m ). , spectromorph won't cut it either .
I think bazille is using it for the spectral stuff
Saw wave is the windowing function (and sync master ) , modulating the (slave) sine osc's . amplitude output , sine frequency is modulated by env for fake frequency sweeps
Example is done in reaktor ( with standard primary modules ) , Talmod can also do this .
It's really simple stuff , but for some reason most sofsynths on the market just miss either on or the other feature to implement it correctly
It goes under various names with minor differences , like paff synthsesis ( phase aligned formant ) , vosim etc, casio cz resonant waves (zebra 's phase distortion effect is fantastic but not for cz resonant style implementations ) ...

Simple audio file ( secure download or preview )
https://app.box.com/s/ggdirysooeho6bzrbwy5qy4ia4rpz9du

