as a Mastering engineer, I've tested many power cords in my Mastering studio, which is likely better resolution than what 99% here have … So I can tell you that yes power cords have a sound. Even Chinese chords, have a slight difference in sound one from the next
It's a question of if it's helpful to your system or not
without understanding what you're trying to accomplish, my general recommendations are the following
1. dedicated line back to the breaker box and install a new circuit breaker, install a outlet upgrade of some kind… I use Shunyata research
2. as far as the power cords themselves, it's not enough to just throw money at it because you think you might be able to upgrade ... you have to have something in mind that you're trying to fix… You have to know where you are and where you're trying to go
Shunyata research is the best value and the best sound quality both so that's a real winner… In order to learn what's going on you could start with two gamma and two Theta NR for $3000. If you have more to spend grab two alpha X If money is not an object, then their latest cable which is omega something or other at $12,000 is the best power cord that anyone has ever made and can be used anywhere
there's plenty of research on this, even if you're nearly deaf, which apparently many people here are
if you don't hear the sound of power cords, or speaker, cables, or resistors, or diode, or capacitors… That doesn't mean you're a bad person, and it doesn't mean that you can enjoy music… It means that either your system is not very advanced, or you're listening skill is not very advanced… This is just a fact of life, and getting defensive about it isn't helping anyone, so please… Just calm down and let the rest of us have a conversation about something we understand well

