I need help on directionality of speaker cables

Carl -- what on earth are you saying? Surely not that there's dc output from yr source I hope -- you risk blowing yr amp.
You must mean s/thing else.

BTW, the mains does have phase, neutral & ground. It also has a frequency, remember -- 50 or 60Hz.

Carl:

My post wasn't meant to sound arrogant, it was more about the apparent muddling of AC and DC in some posts

I got it, I think. You must have read s/where that AC is converted to dc in the power supplies...
However, the electrical signal the devices output is AC as is the input of course. Inputting DC into any of these devices is *dangerous*!!

...but some that go above and beyond simple rules of electronics have great benefit

Tbg: for Goodness sake, you cannot go ABOVE the RULES of electronics -- nor are said rules necessarily simple.
You may go beyond the SIMPLE rules -- but that's neither here nor there.

Cheers