1 Ohm 101

[Trixter 10+ year member]

the xx may be, but not the brutus that the OP is using

the brutus draws about 2x the power an A7 does.

 

[audioholic 5,000+ posts]

Thats why I love my Zed built amps, built in regulated power supply. The amp will put out the same power from 11-15volts

Regulated power supplies have their advanatges, like stable output, yes... but they also have a big disadvantage. That regulated power supply is regulating amplifier performance to whatever it would be given the lowest input voltage available. In other words, if the amp is rated run down to 12volts before going into protection, the amp will always output what it would only given a 12volt input.
You can't make something from nothing, so when using a regulating power supply, it must regulate to the lowest possible output. If your amp had a non-regulated power supply, its output would be more erratic, but also just plain more. Some people prefer this, some people prefer the stability of regulated units like yours.

Cheers.