If you want to evaluate the validity of continuous amplifier power output claims, all that's required is some simple math. In North America, with a typical 15A AC circuit at 120V, you can draw a maximum of 1800 watts. For a 20A circuit you can draw a maximum of 2400 watts. Now that's simply what you can get out of the wall, not what you can get to your speakers, because no amplifier+power supply can be 100% efficient. Class AB amplifiers with linear power supplies typically range from 50-65% and Class D amplifiers can range from 80-95%. So, for a 5-channel Class AB amplifier with 50% efficiency to continuously supply 600 watts to all channels would require 6000 watts from your household AC, not to mention having to dissipate an enormous amount of heat...