Most Beneficial Cable Upgrade


All things being equal, which cable upgrade would have the greatest sonic impact/improvement on a high end audio (stereo) system?
1)Power cables
2)Speaker cables
3)Interconnects
I have heard that power cables have the greatest benefit due to their ability to reduce RFI (radio frequency interference).
Does anyone know the answer to this question?
matjet
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don,t we discuss this once a month? haha i think,,,can,t prove,,, that when i swapped my moderately priced ac cords out of my cd player, pre and amp and replaced with the stock cords that the bass sq went south of he--. i have also done this with the ac cords one at a time with similar results. i gave them a day and it never got better. when i put the moderately priced ac cords back in and listened after playing for a few hours tight defined musical bass returned almost immediatly but got much better over the next day.. can,t prove it but i heard it.. so i have decided that all my cords, cables and wires are going to be the best i want to spend on and leave it at that for now. i also don,t do a/bs because i think i can hear and know what my system and good systems are capable of. i could be wrong.
My point was that when you speak of upgrading it depends on what your upgrading FROM. You can't tell what the weakest link is until you know what the links ARE. That said, anyone who can't hear the difference between power cords in either profoundly deaf or has a crappy system. I have tried substituting cheap cords for good ones many times and have always been disappointed. I wish this was not so as I am as cheap as the next one. I think the reason many systems sound bad is insufficient attention is paid to peripheral gear.
Preamp to amp interconnect, then Speaker cables in my system. I have good PCs but didn't notice a meaningful difference beyond not using the $1 stock cords especially after dedicated circuit.
the question of why does the last 3 feet matter when there are miles of the other stuff out there has not been answered yet