Peter (pbnaudio)
You may remember that I contacted you when you were embarking on that project many summers ago so I am aware of what you were trying to achieve. A switch is indeed the solution.
I have, like hdm, deployed the ancient methodology of plugging and replugging cables: for my test in my 2nd system -which allowed easier access- I used two PI Audio Ueberbuss (as you may know, it uses a passive LC filter in a wooden/resonance free housing) and changed the (outlet) sockets. Tested were Oyaide SWO-XX. Oyaide R1, Synergistic Research Teslaplex / later the SE version, cruzeFIRST Audio Maestro Outlet and Furutech GTX-D Rhodium) . It wasnt easy to remember the nuances as my second system (NAD gear) wasnt up to par with my main rig but I found the Furutech GTX-D(R) the best in my system as it offers both resolution and smoothness. As I have vintage (Duntech/Dunlavy) speakers throughout my house, the GTX-D (R) seems to be the best fit. Runners up were the Oyaide R1 and Maestro (very neutral but not "fast enough" for my taste). Teslaplex SE has lots of speed but is not balanced (too much emphasis on the highs, great for video though).
These were my findings after long hours of listening over a protracted period of time. A few months later I started experimenting with fuses which make a huge difference and are simple to implement if the fuse holder is accessible mostly at the back. I am concluding the test on my NAD M25 in which all stock fuses (incl those in the power section) are replaced by third party ones.
salelectric
as you know, it is the matching of components that matter. I am careful not to use more Furutech in power cords. I have multiple GTX-D(R) in each of my three systems. The NCF has great reviews but I don’t have experience with them yet.
As mentioned above, fuses impart a big signature. Again, it is trial and error. IME I find Audio Horizon’s Platinum Reference better than the SR Black, which is already very, very good. Furutech has great fuses as "entry level" ones but they wouldn’t combine well with fast systems.
As you can see from my other comments, I tried full looms (Audience, HiDiamond, High Fidelity Cables, just to name the last iterations) but never settled long on one brand. Through ever-tweaking - not just power but room correction and isolation/resonance control I am pretty close to "there".
Feel free to contact me directly as I do not peruse the forum on a regular basis.