The molecular level explanation of "cable burn-in"

I think the big miss on the whole snake oil thing is it's very obviously certain that better cable, esp in the extremes (lamp cord for speaker cable like I used when I was a super poor kid).  And there's a large range of improvement.  The only question is how much is worth it.  To me it's simply the law of diminishing returns.  And the good ole subjective, if it works for you then it works.  I think there are many things in our lives where we put some "faith" in things that aren't so tangible but it still makes us feel better and at least have the perception, real or not, that it's better.  More yawn...I know.  lol

Who knows why, but trust your ears.

If you can't tell the difference between cheap and expensive cables, your system isn't very resolving or you've got the speakers in the wrong place.

I’ll make everyone mad.  The main cable doesn’t effect the product it serves.

Instead, a poorly insulated main acts as an antenna and transmits garbage from inside the component it serves under certain circumstances.

You can test this with a cheap main and a cheap interconnect from different devices.  Tape them together for a bit of a run.  You can definitely pick up a hum or hiss or pop. 

In the typical rats’ nest of wires  behind so many audiophile set ups, you’ll get plenty of touching wires with plenty of parallel runs.  Frequently you’ll get some noise.

Run your wires carefully, try not to let them touch, give everything space, and where they have to cross, do so at 90 degrees (or a sharp angle), and use nice, but not exotic, wires, and all such issues disappear. XLR/balanced wiring and components helps a lot, too.  
 

The most sensitive run is from your turntable.  Any issue there is multiplied along and it’s the weakest signal in the chain.  Run it balanced (or however one wants to describe it) if you can.

All the exotic wires, difficult to repeat issues, difficult to test, issues are explained by the above.

Source:  I was an electronic countermeasures officer in a rather long and unpleasant war, and would face things like components working differently when one was placed on top of the other and not the other way around, that no Raytheon engineer could explain but sure as Hell happened consistently. 

@dougthebiker 

“If you can't tell the difference between cheap and expensive cables, your system isn't very resolving or you've got the speakers in the wrong place”

Maybe.  Or the set up doesn’t have the interference the fancy cables are solving in another situation.  Or the components were designed to use the wires being used.

It’s all very situationally dependent.

My mom had alcohol issues and once used a zip cord on me. To her surprise the evidence appeared the next morning in the form of red welts. She put long sleeves on me and buttoned up my top button before sending me off to school.  These days I can appreciate a better cable in a different manner.