Does Power Cord Require Burn-In To Sound Good?

The question is do you hear SQ improvement on other types of cables after break in? If you do, then of course AC cords also need break in. If you don’t, my next question is do you hear SQ improvement after components break in? 
My personal experience with AC cords is thick cables need more time than thin cables. And if you move them around, same rule apply with lesser time.

But I know some do not hear any difference. First you need to be very familiar with the sound of your system. 2nd is analyzing SQ changes  is nothing like listening to music. It does take time to learn what to listen to.

But again, I know non believers will not hear anything different still.

This is a great article - I suggest everyone reads it

https://www.gcaudio.com/tips-tricks/why-power-cables-make-a-difference/

Ha, ha....it doesn't sound different because there is no difference.  Just witness the wiring before and after the power cord.  Hope you didn't get sucked in to spending too much!

However this does not apply to lamp cords.  A better quality lamp cord will definitely improve the color, quality and luminance of the light bulb.  Same concept with refrigerators and washing machines...even fans.

There's theory and there's audibility. In theory, as per AJ van den Hul, who IS an authority on wiring all would agree, any time a wire is even moved, the sound changes. It reverts back if it just moved, unplugged, etc. So of course changing the type of wire changes the sound. The issue is if it is audible, noticeable, etc. The burn in should not be long so long as you keep the wire in place. Try not to touch it with any other wire, and if you must, make it perpendicular at the point where they touch.

I wouldn't spend more than $1-$200 on a power cord. It's not transmitting a signal, just power. The components themselves also filter the power.

The longer the power cord the better, the shorter the speaker cables and interconnects, the better. These are established facts. The main benefit of power conditioners is that you have to plug the cords into somewhere and get some protection against lightning. I didn't hear much if any difference but got the convenience of the 2 issues I just mentioned. They're better than a power strip because they can separate the outlets into different banks. 

Kind of like the Emperor's New Cloths.  I am sure there must be a certain dollar amount that is considered fine enough quality.  I would be more likely to purchase a power conditioner.