The general received wisdom is that if your grand piano stands on a hard floor, whether wood, tile, concrete, etc., the loudness of the instrument can be reduced by putting a thick rug under it. So I’ve had a thick pile synthetic rug under the Omega since it arrived in my home just over three years ago.
About a month ago I pulled the rug out from under the piano to have it steam vacuumed (because my cats love to lounge and play on the rug). I played on the piano while the rug was out and, well, I suddenly had an improved piano. The tonal quality of the lower half of the keyboard was better, less muted (of course). There was consequently a better sense of ‘air’ and resonance that better matched the upper half of the keyboard. In other words, the piano sounded more whole and organic than it already did.
So, the floor under the piano from now on shall remain bare. The cats will just have to make do with the rug some place else less cozy.