Anyone in this hobby knows we have all thrown money away chasing something. The best money I ever spent was in having an electrician put in a dedicated line for my stereo equipment. Next best money was in buying a grounding box and driving a grounding rod into the ground outside the house and then running all my equipment through it. Period. The black background is stark and eerily quiet. I probably have $3,000 in these two things and I would never do it any other way if excellent sound is the goal. Just my .02
Affordable Grounding
My Frankenstereo has assorted grounding elements behind the rack. The head end of the streaming chain is in another room. At the wall outlet, there’s Nordost QBase 4 Mk II – with a ground lug.
I tried this inexpensive grounding tweak clipped on to the lug. Subtle – but it works. More transparency. Probably similar results with the Puritan Ground Master – and other brands. Worth a try! Certainly more affordable than an Entreq. I purchased the cheapest one with the copper wire/paper cylinder. (Not a fan of silver-plated wire.)
YMMV