Doepfer

> > > Most CV voltages in a modular are bipolar, with envelopes and
> > keyboard
> > > the most noteable exceptions. LFO's, S/H and what not all go through
> > > zero. Or more correctly: *can* go through zero.
> >
> > Yes I know that. And that still does not answer my question really..
> > Let's say we have an pseudo-ideal CV> digital converter. It would
> > work from
> > 0 volts to anything, so no upper limit. (Just assume this..)
> > I would shift the CV up by the amount it needs to have the most
>
> In some way you are right, yes.
>
> There are certain CV's which don't yield the same result when "pulled
> down" with a negative bias (like, say, a negative halfwave rectifier),
> but that's not where your theory goes a bit wrong... It's in your
> assumption that there's no upper [voltage] limit [as a way of
> reasoning this through], and that the maximum required voltage is only
> 5 volts. Most, but not all, analog modular systems require +10V to use
> their full range (pitch is a good example). This would mean that your
> device should be able to output +20V to pull that voltage down to the
> required maximum range of +10V (and an additional -10V to have
> bipolarity). Now, what is going to happen when you don't need
> bipolarity ? You are going to send a signal ranging from zero to +20
> volts to the CV inputs of your system ? I'd rather not do that.

No.. me neither but then again I was talking purely hypothetical. ;-)

This is indeed a fascinating subject. And I am very glad that a lot of
people are discussing this now!
Several years ago, when I just joined this list, I was talking about
recording CVs via a method I learned during my studies and how to
implement this with a eurorack system.
People were very much responding "why would you want to do this, there is midi".
I decided to not really push it then..

The method actually was: modulating a VCO with the cv you want to
record and recording that VCO's output. Sending that recording to a
frequency demodulator. And the output would be the CV again. Or at
least something fairy similar.

I now see that it might be possible these days since Analogue Systems
had released their RS35.
For what I believe I read in the manual this is a device that actually
outputs a bi-polar cv in the range of -10v to +6v.

(A word on the studio I studied: They have ALL their control voltages
in the DC range. So no bi-polar hassles there.
Everything is custom build.)