that's cleared up then, thanks guys. the supply that's with it is a bit unclear, just says 9 volts and 750ma, doesn't mention polarity. i never thought to look for AC.
i've lusted after an Electro Harmonix H.O.G. since they first appeared! but they're very expensive. i've nearly gone for it a few times, but it's hard to justify that kind of expense on an effect which i might end up not even using that much. i have a P.O.G. and i think it's very good, so i know the polyphonic thing works. ah, i'll probably end up getting one! :D