But from what I can see the benefit, if there is one, will be most noticeable system wide. In other words, just switching one power cable the way I did before won’t be sufficient for you to tell a difference... again, assuming there is one.
That’s not been my experience. I can hear a difference when one cable/interconnect is changed and determine which one I like better. That’s how I ended up with a full loom of Acoustic Zen cables in my system. Started out with speaker cables, then an interconnect, and so on. Each cable made a positive difference, and as I added more AZ cables the benefits just became additive giving more of what I liked. I’d suggest starting with the interconnect closest to your source component(s) as in my experience I tend to hear the most marked changes there. I also didn’t feel the need to do a blind test. I find changing a cable, going back to the old cable, and then back again to the new cable is usually enough to lock down and solidify my impressions as to which just sounds better and why. Just be honest with yourself and trust your ears, and if the cheaper cable sounds better to you or you don’t hear a significant difference in your system then so be it. The other thing is to use songs that more easily expose various elements of music. One song I used to use is “Muddy Water” from Keb’ Mo’s Slow Down CD as it’s well recorded and is great for assessing cymbals, vocals, bass, imaging, 3D soundstage, dynamics, etc., plus the whole CD is great and fun to listen to. The key is trusting your ears and being honest with yourself about what you really prefer. Anyway, that’s what’s worked for me FWIW. Hope this helps a little, and best of luck.