What kind of power load can the ac jack handle on the rear of a receiver? (sony str-v200 if it makes a difference). As of right now, I have a small sub hooked up to it since this sub doesn't have an auto on feature. I'm wondering if I can plug in a three way splitter into that jack and also plug in my Presonus Firebox (DAC) or possibly even my CD player as well.

I don't know how these things are wired, so I'm not sure if that plug is simply a straight bypass to the main power source, or if splitting it out would be a bad idea for the receiver.