Copper Sleeve over IEC

This is a great tweak that works. I have tweaked the tweak. Before I plug the IEC end of the powercord with the copper coupler on it. I cut a 1 inch strip of Teflon plumbers tape and put it on top of my IEC plug where the three prongs slide in the unit. There is always a space there. If you put the Teflon tape on the outer housing of your IEC plug and not directly on the three prong plug you will fall way short of the best results. In MY system there is an increase in blackness and dynamics to go with the smoothness that the copper coupler brings. Of course make sure the copper coupler is touching the chassis of your unit. Great tweak that works on my Power Amp and Digital player. Will try it on my preamp next.

Why would this have an effect? Does it reduce vibrations of the copper coupler and the chassis?

Tbg, I did not stay at a Holiday Inn Express last night, but my guess is yes it has something to do with reducing vibrations of the copper coupler. With that said, I have been using the Teflon plumbers tape like this for years, And it has always added better dynamics and blackness to the powercords I have used it on. The coupling( pardon the pun) of the two gives you the best of both worlds. It's only an inch long, but I'm sure life has taught us all every inch counts.

I tried it IMS and it rolled off the high frequencies and decreased dynamics so they went back to Home Depot.

Jejaudio, Sorry, but I am not understanding what you are recommending.
Are you putting the teflon tape over the power cord female IEC conductors? Or are you putting it over the the CD Players male IEC conductors? Or what ?