I’ve put together a full version of the Hordijk Sync Oscillator. As usual Hordijk has taken things a step further and turned the irregular transients that were smoothed out with the masking technique, to good use. The transient heights are captured with a sample and hold circuit, and can then be fed back to either the synced oscillator (which generates the well known random S&H pitch effect) or the syncing oscillator (which will change the rate at which the pitches are generated). The combination of the recursive pitch and tempo modulations means that Krell or Rungler-like textures (venturing into noise territory) can easily be generated.
Rob Hordijk provides a nice explanation of how the (true) randomness is generated in his NOVARS tutorial on the oscillator.
An additional aspect is the inclusion of a subsquare divider which can be used to modulate the synced oscillator on every alternate sync cycle. This can be used for the creation of vowel like effects, as well as adding a little bottom end to the synced sounds.
The sample and hold signal can also be applied to the subsquare modulation, and the sync sawtooth, subsquare, and S&H signals also have their own outputs.
I’ve uploaded two demo patches to the Audulus forum.