@erik_squires "In general I believe we should: MInimize the contact surface"
You mean spikes. Indeed. You're talking my language.
Also, remember that if you put your speakers on a concrete floor, that is like a very big stone.
I have a lot of stone and marble in my listening room. All my source and pre-amp equipment stands on it. Power amps and speakers are on low spiked stands on concrete floor. Everything is stone dead when tapped.