Can a power cord increase the resolution of an Class D (SMPS) amp by more than 5% ?

I am wondering where Elizabeth is getting her numbers from 2% not 5% for a power cord.
% of what. You might be able to say that in your opinion an upgrade in speakers sounded 2x better than what you had. Even Audioquest cannot give you a persentage of improvement from one cable to the next. They just say the more expensive the better the sound. Does a Audioquest Redwood give you a 27% better sound quality than an Aspen? Most people in a blind test cannot tell a $300 power cable from an $1,800 cable. Yet people described the difference like one French wine from a CA

I would like Liz to respond and here her comments 

Quiz answer,
Usb and or hdmi in my system.

Kenny.

Oops forgot the dc pwr cables powering my Network devices.

Any frequency other than zero Hz is AC, in that the direction of the current alternates at some rate. Digital signals and analog audio signals both contain a mix of many non-zero frequency components that are simultaneously present. Certain digital signals may have a significant DC component in addition to their AC frequency components, an example being USB signals which have one of their two voltage states at or near zero, and the other at some positive voltage. But a signal having both DC and AC components is nevertheless "operating in an AC circuit," it seems to me.

So the only audio-related cables I can think of which are "not operating in an AC circuit" are cables conducting the outputs of DC power supplies that are external to the component being powered.

Regards,
-- Al

Al,

“But a signal having both DC and AC components is nevertheless "operating in an AC circuit," it seems to me. 


So the only audio-related cables I can think of which are "not operating in an AC circuit" are cables conducting the outputs of DC power supplies that are external to the component being powered.”

This is how I have always understood this too but I may be wrong or missing something also.

As always Thank’s for your well explained statements,
Kenny.