The importance of quality cables is in this sequence. Speaker cables are THE most important and can make the biggest difference, followedby the interconnects, and in last place comes power cords. This is true in my 55 years of listening experience. My house gets clean power so the power conditioner made the least amount of noticable difference.
The Big Misconception About Electricity
This vid goes quite a ways down the road to explaining why:
1) Power cords make a not so subtle difference.
2) Cable elevators should not be looked at askance.
Regards, barts