What difference do power cables make?

@maxwave   Do you have a dedicated line? My experience tells me a dedictated line makes the most audible improvement. Then upgrade the receptacle outlet, now your ready to experiment with different power cords. 

@dayglow 

I do not have a dedicated line , but I have an upgrage receptacle.

My question is about two power cords in a row.

Ps Audio perfectwave AC12 is a 8 gauge ; for my 8 outlets UberBus ( PI Audio) that is fully used.

I wonder if there might be an improvment , to use higherend power cords from the 

8 outlets UberBus to the  audio gears ?Or I am stucked to the Perfectwave AC12 audio level . ( no improvment )

Been asked only 3,000 times..buy one and find out. No one can tell you much of anything, it is system dependant and will vary. It also depends on how good your hearing is. Not trying to be an ass, although some may think I am, who cares. Only you can be the judge if something works or not. I'm sure you can just return it if you hear no difference. 

"The two posters above are imaging things. Confirmation bias at work here! As I've said many times before a component's sound starts with its power supply - not with the wire to the wall outlet. It would be a wonderful world if changing a power cord resulted in a sonic improvement. Alas"

Alas, we have jasonbourne once again with his usual stance - nothing works , everything is imagined.

@maxwave IMO your power conditioner is dictating the SQ NOT the UberBus power cord(PS Audio AC 12) Are all 8 pc’s XLO Signature 3’s? To Answer your question a better power cord will improve your SQ even if plugged in the UberBus. Since I don’t know the level of your system I can’t make an educated guess if the Cardas would be best on the amp/conditioner or source. With my system... 1.power amp 2.source 3.preamp then conditioner