Where do cables upgrades have the most impact?

Why does a manufacturer make and sell multi-thousand dollar amps with exotic power supplies but with power cables that are sub par. I just have a hard time getting past that idea.

Ponder why component manufacturers showcase their products in partnership with any number of aftermarket cable companies?

BTW, you are way past the proverbial 'newbie' status. : )

There is nothing to ponder it's basic marketing. 

@teo_audio  

To try to at least build or modify a single piece of gear. Or that built piece of gear, being modified at least once. In some way. To get an understanding of the complexity of the signal in the boxes. This might be a way.

Point noted. I will move in that direction, holistically.

Both of your posts have been helpful. Thank you!

@almarg  Thanks for your post. All of your 'factors' are important in one's consideration, as I myself recently learned, via you. : )

1extreme,
" Curious if those saying the power cable had the most impact are plugging into a power conditioner or a wall outlet?"

Both