I've tried several different options, using dedicated lines. I was using a Hydra, with an Anaconda, and plugging much into it- phonostage, linestage and amps on one dedicated line. Powered Woofers had their own circuit. And the TT its own. To deal with grounding differences among the circuits, I used a Ground Zero device, which enabled me to quiet the system without having to float any of the grounds.
Now, I have eliminated the Hydra/Anaconda and go straight into the wall. Front end on one circuit; TT on another; amps on a third, which also power the woofers. Still using the Ground Zero device. System never sounded better, but I did change power cords to Joe Kubala's product.