When I bought my first Linn LP12 about 25 years ago, the guy selling it demoed the turntable with a Ringmat. It sounded awful - thin, lightweight, no midrange. I was disappointed and asked him to put the stock felt mat back on and suddenly the LP12 magic returned. It sounded great and I bought the turntable - with stock mat (that TT is now sadly long gone).
Years later I bought a Ringmat to try myself and had exactly the same experience with a few different turntables.
It was one of those tweaks that became popular for a few years and got good reviews - as happens often in the faddish world of hi fi - and then thankfully disappeared without trace.
To the OP, live with the Ringmat for a while. My guess is that in a few weeks or months you will remember why you put the Ringmat away years ago.
Years later I bought a Ringmat to try myself and had exactly the same experience with a few different turntables.
It was one of those tweaks that became popular for a few years and got good reviews - as happens often in the faddish world of hi fi - and then thankfully disappeared without trace.
To the OP, live with the Ringmat for a while. My guess is that in a few weeks or months you will remember why you put the Ringmat away years ago.