Why power cable effect overall syste sound?


Power cables effect the system sound. This is a well-known fact. My question is why.. specially in case of low power type "A" amplifiers where current is constant. In my single ended 300B the cable creates huge difference. Does it points on power supply PSRR issue? Actually in case of well designed power supply, the power cable should not introduce any improvement. We are spending hundreds of dollars for the 1 meter of cable from outlet to IEG socket where meters of cheap wires running in the walls and it does work. The answer on this question is puzzling me.
abronfer
Power cables effect the system sound. This is a well-known fact.

Its not a well known fact...please state where and when this fact became well known...? It only works acordingly to justify the spending of hundreds and sometimes"God Help" thousands on 8awg copper wire.The power cords that come with your unit are all sufficient in delivering what is needed, adequate current.
Not true Schipo,my DIY 0000awg power cable takes my playstation to another planet.:)