12 volts aparently.... I was told this from some dumb kid who opened a new shop with daddys money.... Hes an authorized soundstream dealer and thinks he can run full power, to his 6500 .... now(soon to be) 10kw.. off stock electrical.. I told him hes crazy if he thinks this is possible, and from what i know of those amps there more of a 16v setup.... But what do i try to tell this idiot ? he does'nt listen to reason and still believes his xxx6500 is putting out full power, fyi his light dont even dim aparently