What is the maximum current draw from each amp? Can the power conditioner handle it? can the wires back to your service panel handle all that current/power on one line? this is really not a good idea electrically. I know this is not what you may want to read/see, but you really would be better off electrically and sonically if you have dedicated lines with separate neutrals going back to your service panel. Small signal electronics such as pre-amp, tuner, cd player, turn table can be plugged into the conditioner and that conditioner has its own dedicated line back to the panel. Each amp should have a dedicated line back to panel. Ground loops are eliminated and electrically, your home's electrical system and wires are correct, and also important, sonically, this is much much better.
It really doesn't cost much for a qualified electrician to do this and you can do it yourself if you follow the proper procedures. Regardless of what kind of conditioner you use, the power/current draw on that one set of wires would be not a good idea. Dedicated lines are the way to go.
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