Which power cords have high resolutions and separation??

From my very limited experience, I'd say you have a bit of tunnel vision here, Jerry. The cord I mentioned above has a 60 day risk-free trial. Looks like zero downside. And to be clear, I think you're spot on with your comment of wanting a cable that doesn't take anything away.

Lots of evidence of this these days aside of power cables,tone controls.

None of them, but believe what you want.

Take your pick of any good quality wire.  Need not cost much.   For power amps current delivery is more important.   For line and phono level and digital devices, shielding is a good thing.