From the youtube message:
This is another surprising result using feedback. Two panned sawtooth oscillators are going through sync operations, with the depth being swept from maximum to minimum by clocked LFOs. It turns out that at the bottom of the sweep you get very different sounds when the sync feedback is all the way up.There’s also a clocked envelope making sure the emphasis is on the oddball tones, and some oscillator 3 and ring mod. One note is held, there’s no pitch shifting.
In theory both oscillators should be making the same noises, but I guess there’s enough chaos going on in the Hydrasynth to get differing results. No analog feel, no random phase.
Interesting trick, I was able to duplicate this more or less, in about 5 minutes – though it doesn’t sound quite as nice. I will keep experimenting.
Not sure of the cause either, perhaps it is from a chaotic instability as the creator Michael Rohaly suggests or some other unpredictable factor. The idea of a chaos generator on a “deterministic” digital synth appeals to me. The HS always seems to have that sort of a analog randomness to it, which often comes when i am least expecting it.
Oscillator Sync is a Mutant operation of course.