Help!

I am about to buy Fran's DigiTech Vocalist Workstation, but first I need to know if my KN6500 will accept it, as there is already a "Harmoniser" on board. (Albeit a most inferior one!) There seems to be no reference in the owner's manual, or on screen, to connecting this device. Would I be able to use it? I do know that on the KN5000 it is connected via the MIDI interface, but that's the extent of it. Also, is its voltage compatible with South Africa's 220V AC current?

Neil Bennett