I would like to share some great results I have had with power supply to my sound system.
I was on the verge of spending a lot of money to purchase some furutech plugs and expensive shielded cable to make some leads. As i made some speaker cables recently that have with time come along very nicely.
After thinking about it logically I realised that these cables can't change the stuff coming out of the wall socket, at best they can preserve it.
I ended up running a new power lead to the mains in my building from a dedicated socket near my stereo.
I can say without any doubt there is an improvement in sound quality. For the cost of the wiring I would recommend to anyone thinking of spending money to upgrade equipment to try this first.
I don't have an explanation for the improvement,possibly being in an apartment there is a lot of equipment operating off limited resources