While I think a lot of these AC issues have local environmental elements that may determine effectiveness and the right components to help, I do own several iFi AC purifiers, including those that came with the iFi Powerstation, and they made a real difference in my home.
The AC Purifiers helped bring greater depth, greater air around instruments, and even (and I was really surprised with this) added a bit more natural tonality to instruments.
They are not that expensive and are available on Amazon, so they might be worth trying one or two in your setup.
Least expensive plug-in power conditioner that works
I am currently using a Shunyata Venom defender on my main system with good results. I’d like to put a similar device on the power to my Internet modem that’s in a separate room. I notice that there a lot more choices in this product category now. Does anyone have any recommendations that are cost effective and make a difference in performance?