I am improving my piano practice room and I found recently the Piattino Sound Proofing Castor Cup.
These work, as far as I understand, by absorbing vibration from the piano to the structures around and therefor avoiding structural transmission. I am trying to avoid noise from getting to my neighbours.
I have already put a couple of rugs under my piano, and I can still feel some vibration on the floor so I believe I can benefit from such a solution where vibration is absorbed.
In any case, how good are these? Are there equivalent solutions with a better cost?