I have one Mat on top of my resolution audio opus21 CD player and it has dropped the noise floor dramatically while making the music more dramatic, impactful and engaging throughout the frequency spectrum. The soundstage is the first thing I immediately noticed after it was installed. The dynamics etc... came one day after it was installed. I will not be removing it.
I thought that it sounded so good that I ordered a second one for my office system dac.
Enjoying the music,
rc