FWIW, I posted yesterday to find out if the Marantz AV550 pre/pro could trigger on my Parasound 2003A amp. I actually received an email back from Marantz stating that the voltage output from the Marantz is 5 volts, which is not the required 12 volts that the Parasound requires. I tried the connection with an old RCA jack plugged into the Marantz and the other end I cut the jack off and hooked it to the Parasound amp. The Parasound tried to turn on, as there was an audible click, but I guess there is not enough voltage. I just thought I would post my results so they can be deleted again when the server crashes Just kidding.