@ozzy , my new Audioquest Dragon Source cords (3) have just now reached the point where I cannot hear / perceive any difference between them and the fully burned-in demo cord I had on hand along the way. They have been cooking for just over 400 hours now. Prior to 360 hours, there was a blatantly discernible difference when I swapped in the single burned in demo cord, replacing just one of my three new cords in my system. Yes, the difference was night and day.
I have to admit, even though I firmly believe in burn in from my past experiences (or perceptions if you prefer, I consider both terms to apply to my subjective experience), I had started to wonder if something else was at play that would explain the difference I was hearing between the new and burned in cord as of 360 hours and prior. I was wondering if maybe the design had changed, tolerances were coming into play, etc. But thankfully my new cord sounds equivalent to the burned in demo cord now. That is to say (here come the SUBJECTIVE descriptors) that it is more open and relaxed, the images are more solidly defined, there is a more relaxed soundstage which means that there is more depth and layering, and there is more unconstrained high frequency detail coming through, in a relaxed and gentle manner (e.g. decay on subtle cymbals are more defined now and trail off in a more 3D space without the sense that the brakes are being pumped). There is less of a sense of restraint overall, and also I am hearing more resolution, seemingly due to less noise.
All in my head? I was on a hike on the weekend and we passed a guy who said to his companion “Point to a tree and I’ll prove to you that it doesn’t truly exist.” Not sure what the context was and unfortunately I didn’t stick around to hear his “proof”. But at a certain point I need to have faith in my subjective perception of the difference between the burned in and new power cords.