Yeah, it’s a mid-supply reference voltage, used to bias the transistor inputs. I think virtual ground is a bit of a misnomer, though, unless perhaps if you always power the circuit with batteries and make sure both rails are always floating.
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The schematics look odd because they seem to be drawn from right to left and having positive supplies at the bottom while gnd is at the top, which I assume is not a conincidence. If you reverse that they will be easier to interpret. The transistor at the top right of all diagrams has emitter and collector connected to GND while it it fed a bias current via a potentiometer. That bit of the circuit does not make a lot of sense to me.
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I’m really grateful for the work people are doing on this thread (and elsewhere) to turn the pretty but often chaotic Ciat-Lonbarde designs into something a normal person can understand.
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This is the 6-Roolz schematic without the Serge section (multi-vibrator)
The roolz power runs counter clock-wise and the resistor values on the Hairy Capacitors descend in Clockwise rotation…
Peter is fucking weird… Some of his stuff makes little to no sense but produces amazing “noise” 
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as for drawing the schematics right to left, I guess I’ve never learned how to draw schematics lol.
So this is the way it seemed correct in my brain…
Or are you referring to peter’s hand drawn schematic?
Here is his schematic for deerhorn…
I havent even bothered with this one… lol
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@fredrik
Like this?
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Yep, that look much more conventional. Although functionally the same, if you’ve been looking at various schematics for a while, you ‘discover’ that there are certain conventions a lot of people adhere to which makes it easier to understand the next circuit you look at and find circuit parts with specific functions.
Drawing a schematic like the curly one is not unlike writing obfuscated code. Functionally that is the same as ‘normal’ code but it is more difficult to read for humans ( not for computers ).
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Obfuscation is of course the entire point here.
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Yeah, that opamp should give you a nice mid-supply rail. You could probably increase the voltage divider resistor values a bit, but it doesn’t use a lot of current as is, so should work just fine.
(the resistors don’t just form a voltage divider, they also keep the capacitor charged which helps dealing with 9V ripple – if you remove the cap, the opamp will faithfully pass on 50% of the ripple, which is a bit more than the 0.001% or so that makes it through via the opamp supply rails)
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I appreciate your responses so much @fredrik 
Thanks again
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Looks like an electronic flower!
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Looks so dope! Question I’ll ask here cause I’m sure others would find useful as well…how do you rotate components in ways other than 90*? Or get non linear traces?
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so there are a couple ways to do it - click on the component itself and hit CTRL + M and it will open a move box for x, y, and Rotate - you can rotate it however far you want there.
Or - CTRL - R on certain components and you can set its rotation in the lower left
I believe in normal view it is CTRL - R and CTRL-M and in Foot Print Editor only CTRL + M works… lol
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The non linear traces - I use WireIt for a Plugin and create my own nets.
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Just make sure the demons you summon with that thing pay rent.
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What do the control signals look like? Voltages, pulses or gates, etc.?
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some of the waveforms are presented on this page -
http://ciat-lonbarde.net/rollz5/
Some raw - some post ultrasound filter.
I am actually getting an old scope hopefully soon, will have to check it out on there - pretty sure my DSO-138 stopped working lol
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And they are Pulses from my understanding.
When I get into the CV Rollz boards - those will generate CV
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