Mike Powell of Verastarr.com sells what you ask about. His product is named Starrdamp, and one side of it is copper which also shields from RFI.
He is currently having a closeout on his mass loading granite blocks which are another aspect of tuning and clarifying.
I have used both of his products in a few of my systems with fine audible improvement.
Herbie's Audio Lab also has great products which you can read about on Herbiesaudiolab.com. I use in a few of my systems and the product line is extremely broad, and addictive.
Both sites list phone contact numbers to speak with the owner. ("Herbie" is a nom de plume) Both are dedicated audiophiles who spend time with a caller.
He is currently having a closeout on his mass loading granite blocks which are another aspect of tuning and clarifying.
I have used both of his products in a few of my systems with fine audible improvement.
Herbie's Audio Lab also has great products which you can read about on Herbiesaudiolab.com. I use in a few of my systems and the product line is extremely broad, and addictive.
Both sites list phone contact numbers to speak with the owner. ("Herbie" is a nom de plume) Both are dedicated audiophiles who spend time with a caller.