Burn in period

When a cable wire is formed it's drawn through a die. This aligns the metal in a certain direction so this is why manufacturers believe cables are directional.

They should follow the way they were formed/forged.

Hope this helps.

I wanted to add, I saw a show on building transformers, I think it was transformers. The first thing they did was find the correct direction for the coil wire before feeding it to the winding machine. So it must have some validity even if it's not audible. 

I do hear difference when cables broken in or equipment burned in, but my cousin who is top notch physicist with bunch of patents in signal traveling area of physics including space staff and lasers laughs at me when I mention cable beak up problem, however he agreed with equipment burning in necessity.

@yugebohner 

hahaha I was waiting for someone to pick up and further development on my asparagus post.

Isn't audio signal an AC current?  Directional?  explain please.