It would help me a lot to help you if you could upload the patch here that you’re using so I can see how you’ve wired it.
Basically, Audulus’ maximum I/O range is scaled -1 to 1, and the ES-8’s maximum is -10 to 10 volts.
That means each 0.1 increment in Audulus is 1 volt.
Also, -0.1 is -1 volts.
So if you have a signal coming in that’s 8 volts, it will be represented as 0.8 once its in Audulus. If that’s what you see when you turn a stages stage all the way up, then I was correct in diagnosing the problem you were having.
The rest about understanding the octave signal, you can watch the VCO videos and check out the corresponding tutorial patches here:
https://discourse.audulus.com/t/module-library-tutorial/3129