You can use a regular instrument cable. Just make sure it's plugged up to a speaker load.
Rhodes Gemini
Fryette Ultra Lead
Peavey 6505
THD Flexi 50

Gibson R0 Prototype
EBMM JP13 Rosewood
Fender CS Mary Kaye


(512) Audio Engineering - Custom Pedal Builds, Mods and Repairs
An instrument cable is good, and yes, you can plug straight into a board or whatever you like with it.