Yeah, mono coherence/correlation is one of the parts of sound design and psychoacoustics that I find extremely fascinating. Back when I was in school I liked to make my drum kits sound miles wide... then one of my profs collapsed a project of mine to mono, held up a thumbs-down and made a farting sound with his mouth. That was embarrassing. I know better than that (mostly), these days, hahaha.

On the topic of the classic oscillators' Shape parameter, I'm curious about something: Since it serves to add harmonics (changing a sine or triangle into a saw and then to a pulse wave as it's increased), would it be correct to say that it can create a similar effect to a lowpass filter? For example, applying a sharp, plucky envelope, inverted, to the shape of a classic oscillator set to sawtooth, should have a similar effect to applying the same sharp envelope to a lowpass filter for a 'pluck' sound?

So the 'Random' modulation source changes on each key press? That's really good to know. Man, there are so many modulation sources on this synth that can be used in really, really awesome ways.

^well, it morphs to the wave that's selected. so if that's a sine wave, you'd have something similar to a low pass filter going from saw to sine, yes. you can create a perfect sine with a sawtooth if you filter it enough - check with oscilloscope. you do have more filters on the fx section, on distortion - I think the TI keeps it just so that it can reproduce older presets, but it can have its uses.

that experiment would result in a similar sound, but not exactly the same as having a pure sawtooth with a plucky envelope modulating a low pass - sort like the trance standard bass patch. 'cause then you'd have to take into account the characteristics of the filter, that's some steps beyond simply adding and removing harmonics, specially if there's some resonance on it.

yeah, random changes with each note - different from Sample&Hold LFO in that department, even though if you had all your notes snapped to a grid, you could presumably achieve the same effect with it if it was synced to that grid tempo...

the fun thing about the Virus is that this frame of mind tends to come and stay: it seems like some pretty regular subtractive synth at first, but then there's much more to it and it's inspiring to explore all the holes in it.