Hi Michael,
Not sure how much this may help but hopefully at least it will be an interesting story.
Many years ago, not long after the trend for replacing stock AC cables with "upgraded" cables became established, I was curious but skeptical. So when a friend who was a small scale high end manufacturer recommended some modestly priced upgrade cables I gave them a try. The biggest surprise came with my Sony ES CD player. That had a fixed AC cable, but I'd ordered one of the recommended cables with a 3-pin receptacle on one end in place of the IEC connector. That meant the standard cord remained in place but the connection to the wall was then with the upgraded cable. I'll be d*mned if the addition of the upgraded cable didn't sound better. Sorry but that was so long ago I can't offer specifics, but I think improved clarity and slightly better dynamics.
What could I take away from that? I don't have any more than average knowledge of electronics but it seemed the added cable must be filtering junk from the AC feed since any otherwise restrictions/limitations in the stock cable were still in place.
That was good enough for me to begin utilizing replacement AC cables. I just don't believe in spending more for the cables than the component cost on it's own.
