Just a thought to share.
In my case, a few years ago I was enjoying my ARC based system when it started to sound constrained. I did some looking, and couldn’t really see any obvious issues that would cause the flattening and less than lifelike sound. Then one afternoon during this period my ARC Ref 6 shut itself down. It went into a protective mode. The cause was LOW voltage. I got out power monitoring equipment and discovered voltage drops to below 95 VAC. Our power is provided by TVA which is usually a reliable supplier.
I was running AQ Niagara power conditioners at the time. Over the course of the next few days, I saw voltage swings from 90 VAC all the way to 140 VAC. My Niagara gear could smooth and clamp, but it could not fix very low voltage.
I had been skeptical of regeneration up to this point, but I decided to try a used PS Audio regenerator. I was quite surprised by its excellent result. ARC recommends that their gear sounds best at 117.5 VAC. On this regenerator setting, my ears told me that their recommendation was quite good.
Shortly thereafter, I traded some gear to PS Audio for a new P20. The P20 has more than enough outlets for your purpose.
Regeneration is the only strategy I know short of building your own power plant, that can protect you from low voltage swings. I am very pleased with mine. I run a P20 at the main part of the system (now based on Burmester rather than ARC). My phono gear is remotely located, and I run my used P12 in that location to power my ARC Ref Phono 3SE and turntables.
I highly recommend a regenerator trial. PS Audio has a generous trade policy as well as a very generous no risk trial period.
FWIW, my conradjohnson gear did not respond positively to the regenerator, so in my opinion, it is necessary to have the no risk trial period. YMMV