@temporal_dissident; I suggest you do exactly what you stated at the beginning of your post with the five points you listed.
"Is there some more objective way to A/B test power cords and interconnects?"
Although you will receive a number of different answers I'd say keep life simple and fun and enjoy the music as you make comparisons.
"Is there some more objective way to A/B test power cords and interconnects?"
Although you will receive a number of different answers I'd say keep life simple and fun and enjoy the music as you make comparisons.