Makes no sense to me.
What do you have, what do you want?
As an example:
I have: Analog signal, -10V...10V
I want: Analog signal, 0...5V
That's something we can solve.
You probably know what you are talking about when saying "the trigger input from the synth" or "The control voltage varies in a stepped manner. (Switching between 8 outputs)?"
I have no clue.