Furukawa power cables

I have a Spectral preamp that has an outboard power supply with cheap factory cabling into and out if the the power box and have tried upgrading the cables and there was no audible difference in sound.I have an expensive set up and have upgraded most of the power cables but spending more than $100 to get decent connectors and shielding is useless.The power comes from the plant down the power lines into the house wiring addding a firehose $5000 per cable is ridiculous.The very best audio equipment is not improved by adding 3' of ultra expensive power cable from the wall plug to the input.

@peterfd unless you have an under-gaged, high impedance power cable. But if you have a low impedance power source, or some type of shielding, or... it can make a lot of difference.

At the very least a good power cable can help you to reduce REFI near the component, no?

@peterfd. I too use Spectral. Why do you make your claim? What power cords have you tried?

Buy I cable and get a free Egg Roll or LO Main.

I did buy the cable and it seems okay, though I have been trying to learn whether the amount of shielding is adequate to be any use.

I got it from Aliexpress, called:

Hi-End Furukawa T1 5N OFC copper multi conductor power wire