Power conditioners

APC make a reasonably proced unit specifically for AV applications too.

A power conditioner reduces noise by filtering the power. These also include surge protection.

A stabilizer will step up or down the power to keep the voltage closer to 120 Volts. If you have severe swings in power then a stabilizer is a good idea, it will help protect your equipment - so it will last longer.

Generally you should not use a power conditioner with a power amp, however, some devices are designed and tested to work with power amps.

An AC regenerator takes the incoming ac converts it to dc then back to ac. Generally they maintain the ac at a constant 120 sine wave. Examples APS Purepower, and PS Audio Premier Power Plant; Monarchy Audio has a less expensive version.

It really depends on your particular setup. You don't know the benefits that you will reap until you try different units with your gear.

I tried several Power conditioners. I have settled into an APC S20 Power conditioner with battery back up. Detroit Edison provides very dirty power. Brownouts in peak summer hours wreak havoc on my preamp. The APC unit cured the brownout issue. Surprisingly excellent performance for it's price point. I have gotten very good result from replacing the stock cord with a Virtual Dynamics Nite power cord.

I have my whole system plugged into the APC, dynamics and bass response are not limited in any way. Huge jump in dynamics and bass when I swapped out the stock power cord for the Virtual Dynamics cord.