@guakus ,
I don’t know if a difference in sound can be heard, from say a power amp, whether the conductors of a power cord are copper or silver. (Interconnects and speaker cables, are a different story.)
Things that can make a difference in a power cord:
The wire gauge used for the conductors.
Solid core or stranded wire conductors.
Geometry, how the cable is made.
Shielding.... Can be good and can be bad. Depends on the application, the equipment it is used to feed.
The type and quality of the connectors used.
As for the speed of current through a conductor, in a circuit. It’s travel is very slow. As slow as molasses.
You may find these exchanges of some interest.
2x200W amp might take from mains close to 1kW during peaks. The problem is that peak supply current won’t be expected 8A, but rather close to 40A. It is because current is drawn only for very short time (millisecond pulse) at the peak of full wave rectified sinewave. It applies to most of LPS. Power delivered with such short pulses not only creates larger voltage drops in house wiring, but also heat-up amp’s power transformer, that has to be oversized (higher copper losses and higher core losses for eddy currents and hysteresis).
@kijanki
+1
Please explain what happens if the power transformer’s secondary winding voltage is lower feeding the rectifier, due to a quick AC mains VD event, and the electrolytic capacitors voltage is higher. Just going from memory the rectifier will not conduct and the caps do not get recharged for that "(millisecond pulse)" in time.
Jim
@jea48 You are right - there will be no current thru rectifiers until capacitor voltage will drop below rectifier supplied peak voltage. Theoretically it is possible to build LPS where capacitors keep average instead of peak voltage, but it requires huge inductor in series (in order of Henries) made with thick wire and AFAIK nobody is doing it. One problem is lower rail voltage (average instead of peak) while the other is dependency on the load current.
http://www.r-type.org/articles/art-144.htm
Circuit wire gauge size matters.
.