I have my subwoofer and my reciever plugged into my power conditionner APC H10. Haven't see any problem at this time and i feel more safety when storm comming. Sometime i can see it work hard. Isn't a good way to regulate your voltage and avoid spikes ?

There's nothing wrong with surge suppressors, but "conditioners" often have a transformer of their own, which when placed before a high-draw device like a sub or amp, will limit current and hurt performance. Only if the conditioner states that it is not current limiting, should it be used before anything with a large amplifier.

Of course some esoteric, several thousand dollar power distributors (like the Weizhi Precision PRS-6), do nothing, so they're safe to use. Not that anyone should buy one in the first place.

Scott, welcome and let me point out that "the power supply of the subwoofer amplifier does all the 'conditioning' required of the incoming AC signal".

Okay, now that I've performed my basic function, I'll expand the comment. Amplifiers don't use the power that comes out of the wall socket. The transformer, rectifier and filter capacitors in the power supply section of the amplifier "condition" the AC which may be more or less "dirty" into clean DC for the output transistors to add to the incoming voltage signal to make it about 25-30 times stronger so that it can drive a speaker at a usable volume level. The result is that when these amplifiers/receivers are tested, the noise level is inaudibly low, regardless of the condition of the power coming out of the wall.

One of Monster's scams used to be(don't know if they still run it)that the salesman would plug the Monster noise analyser directly into the wall socket in front of the sucker(er, customer)and then smile while it vigorously hummed and howled. Then it was instead plugged into the Monster "conditioner" which was plugged into the same wall socket, and of course it was now quiet as a lamb.

Standard cords of 18ga(as Philippe mentioned)or thicker have plenty of capacity for the needs of audio equipment(a hair dryer is a tougher task), so use what you have or buy another for a few dollars.

The salesman are still working hard pushing the high margin/high commission power conditioners, cables, screen cleaner and extended warranties on the poor unsuspecting consumers.

I received that same spiel/demonstration when I purchased my LCD. Of course they sold every possible Monster product on the market.