It depends on what country the SNES is from.
The North American SNES and Japanese Super Famicom require 9-10 volts DC input, whereas the PAL SNES consoles need 9 volts *AC*. (This is a weird anomaly carried over from the NES.)
The US and Japanese machines have exactly the same video output too. In fact, the two consoles are internally identical, it's only the plastic outer shell that's different.
Mike