10 gauge is a good idea for an amplifier that intermittently draws much current to power loud passages, but for class A such as SET, it is not necessary. Before you spend on "clean power" AC regenerators or filters do you hear all the claimed "dirty" noise when your amplifier is on with no source playing; e.g. phono without a record playing? AC power strips which may have filters have value for the insurance of surge and spike protection, including such protection for FM antenna cables in case of lightning.
Keep in mind another thing. The ripple filter in the power supplies in your components become more effective at higher frequency "dirt." Such noise can be written as a Fourier series of the fundamental frequency above 120 Hz and the higher frequency harmonics are not only much lower, the reactance of the power supply capacitors in inversely proportional to the frequency and the reactance of the inductors is proportional to the frequency. The power supply ripple filter, which is already good enough to make 120 Hz inaudible allows less of the higher frequency lower voltage Fourier series terms get through. It does this better than any power box costing thousands of dollars.