[sdiy] CV and current Boss guitar multifx boxes?

[Paul Perry]

Does anyone know exactly what a Boss multifx box expects to see on its 
control input? I think it is a variable resistance, but can anyone 
confirm this, and if so, what resistance range does it expect?
I have been asked to control one via CV, so I'm thinking of a current convertor
and a led/ldr setup. I can't get inside the fx box (and, don't wnat to!)

paul perry Melbourne Australia