That looks about right.
The source makes no difference regarding your amp's power consumption. An amplifier is a strange device. It isn't like a car which uses no gas when it's parked in the garage. A better analogy is an escalator. It's running whether there are any people on it or not. Yes, an escalator's motors will draw more current when it's loaded with the weight of people but not that much more. The same thing is true with an amp. It uses 70-80% of its full power consumption even at idle, and in a home theater set-up, make that power consumption times five. It gets even worse. If your amp is a seven channel amp and you only have five speakers hooked up to it, it's still running all seven channels. You are powering two channels of amplification you aren't even using.
As for the last line of your attachment, Kevin, one of the basic electronic formulas is P = I x E, or power equals current times voltage. If your amp is drawing 11.8 amps of current, which is high but not outrageously so as I have an amp that also draws that much current, multiply that by 115 volts of AC power. You end up with 1357 watts of power consumed, which is more than the spec.
