Don't change power cables because doing so well do NOTHING to the sound. It's fake news. And if you've got 12AWG OFC cables, no amount of money can but any cables that will ever sound better, or different. Again, it's all marketing. All of it. Anyone who says otherwise is part of the problem.
Fine tuning the system. Where do you start and how do you proceed ?
It sounds good and yet..
Leaving wall current alone - it’s a separate big problem. Leaving the room alone too.
Do you begin by seeking out best LP pressings ? Or tube rolling ? Or cables and power cords comparisons ? Isolation devices perhaps ? Something else ?
How do you go about it ?
I tend to start from the beginning - LP pressings.