When using a power conditioner, why is it advised to run amps directly to the wall?

@wfowenmd zlone’s response is unclear to me. Did the PS Audio improve or degrade the SQ from his amplifier?

Apologies if I was not clear. Yes, there was a definite and positive difference when I moved the amplifier directly to the wall.

@audphile1 Your experience with the Puritan was the same as mine. Noisy.

In the end it comes down to listening over time to decide what works best for you. In my case the regenerator is the best solution I have tried to date for my front end components. It is not a jaw dropping difference, but an incremental and consistent improvement in my system.

I am one who is stymied by PS Audio using the word "regenerator" to describe that product. I would think most would actually believe it is recreating electricity that is better than what the electric company is providing you. Far from it, right? Atmasphere stated in another recent thread here that any of that kind of engineering ended in the 1980's. Power conditioning under the guise of regenerating.

And, Erik, why would you need voltage regulation if you have a unit (Panamax) that provides voltage monitoring. If you monitor your voltage and there is no fluctuation, you would not need regulation - surmising it is plugged into the same outlet/circuit at all times. With surge suppression on the other side of it, if a spike were to occur, the protection is the same in anything you use.

I was surprised at your affiliate link - that Furman is 49% off!! If you need a voltage regulator that is a great price.

PS Audio's power regenerators work by converting AC from the wall to DC (just like your amp's power supply does), then converting DC back to AC. So its output stage is essentially a large amplifier outputting a 50 or 60 Hz sine wave at the chosen voltage.

Which means that, theoretically, a power regenerator can output any kind of AC power since it is synthesizing it from DC. Think of the possibilities: You can take your entire system with you when your company relocates you to Europe and use it there as-is, or you could buy a full Accuphase stack from Japan and your power regenerator will feed it pure 100V 50 Hz AC power.

Interestingly, the old PS Audio (P300 and such) used to do just that, whereas newer models merely duplicate the incoming voltage and frequency. 

My statement "Engineers can work the problem out" does not hold water very well. How could you test your product in every conceivable way with the number of possible configurations of equipment, including power conditioners, cables out there? Its possibilities are exponential, which is true with everything in audio. Makes everyone's position right or wrong at some point in their posts.

This is where engineers earn their keep trying to figure out the best approaches to designing and testing.