Edit: By the way, you say the PP2 CAN go underneath? I just checked your website and it says that this can only be done with the pro.
Not sure, but check out the Pedal Power manual..I believe that there is a DIP switch for each 9V output that, when thrown, bumps up the standard 9 VDC voltage to old Boss adapter specs, which is 12.2 volts.
joe