My PC’s power cord broke, and I thought I’ll take a look. Seemed like a standard stuff, AWG18 (or cross section of 0.75mm squared):

Then I cut it and what I found was very strange:

Strands of wire were all oxidized and cross section looked more like AWG24 (0.25mm sq). On top of that they were kinda “springy”, I could not twist them together. Insulation is rubbery and soft. Really bad. Just to make sure, I made a trip to the local store and bought standard cable, again AWG18 (0.75mm):

The difference is dramatic, in the cross section, color of the Copper, quality of insulation... best illustrated by the image below:

I have seen all kinds of wire, but this is handily the worst, by far.
I can only guess that if I compared the two power cords in my system, they would sound very different
