Currently the FM input is tied through an attenuator into the
exponential CV buss to provide exponential FM. This was done to
facilitate the use of the VCO in a modular system where most of the
control voltage sources are already linear. It is simple enough to bend
the frequency down to DC. In an expo VCO linear FM is typically used
for linear detune which the secret to obtaining what Jurgen (Haible)
describes as "living VCOs." I can add a switch-selectable linear/expo
FM option easily enough, though it adds like $15 to the end price.
Crow
/∗∗/
On 11/15/2011 1:17 PM, David Rogoff wrote:
> Excellent! One thing (of course) - one of the coolest effects on a CS
> is bending chords down to dc, which is possible since the VCOs are
> linear, not exponential. I hope the FM input jack will allow this.
> Maybe 0 volts is freq ∗ 1 (no mod), +5v is freq ∗ 2 (+1 octave) and -5v
> is freq ∗ 0. This would work like the ribbon on the CS80/60.
>
> David
>
>