Power amp protection and filtering

A regenerator is much more than a filter. It actually creates a whole new waveform so that your equipment does not have to deal with the voltage sag that happens near the peak of the sinewave. The big concern with regenerators is that you need a big enough one that can easily handle the current demands of you system..... As far as filters go, some can negatively impact the sound although in most cases they do improve it. Just make sure you can return it if results not good for your system.

A regenerator circuit does not have infinite power. It is common for them to not be very happy with tube amps of higher power. This seems to be because they don't like heavy loads that have a lot of constant current, and your ARC has a substantial filament circuit.

FWIW there is a company called Elgar that made the world's best power conditioners **bar none**. They don't make them anymore, so you would have to look for one used and have it rebuilt. But the big one could run 28Amps of current continuously and put out a perfect sine wave. I think they made a smaller one that was rated at 15Amps as well.

They are mechanically noisy so what people usually do is install them by the home's breaker box, and run the line for the audio room off of the conditioner.

"This is what is inside your Hydra:
http://www.10audio.com/diy_power_conditioner.htm"

Actually, that piece written isn't entirely true. The author is making quite a few assumptions. I do not care for Jerry Seigel at all and I certainly do not trust anything he writes. In MY system, The Hydra 2 was a very worthwhile addition.