Voltage stabilizer for big amps??

I have noticed that my ARC VT150SE amps sound best when my home line voltage is at or above 113 volts. These amps have an input voltage meter on the front, and the sound deteriorates when the voltage drops significantly. Here in California (power crunch, you know) line voltage drops are a part of life... do any of you have experience with voltage stabilizers that might accommodate big power amps? The VT150 can draw as much as 550 watts each. I use a PS Audio P300 for my line level gear, but their P1200 is really expensive; I think that the P600 is not powerful enough. Monster cable makes a voltage stabilizer too, have any of you tried it? Thanks for your opinions.. M