Granite Bases for Vandersteen speakers

These things work great. Too bad they are out of stock. https://www.amazon.sg/Douk-Audio-Isolation-Amplifier-Turntable/dp/B07K9ZYP84 Search around, others might have them.

Sorry, did not know Vandersteen were hyper coherent. That being the case springs will work even better. They do nothing to alter timing, just to eliminate ringing.

You're right about granite, it does all you say. Yours are custom cut versions of the machinists top plate that have been under my turntable and amp for many years.  https://systems.audiogon.com/systems/8367

Something I always suspected, but it took many years to hear it, granite imparts a hard edge. Always suspected, because hit it and it makes a high pitched ting or tink type sound. So its there, but might be hard to hear right now. It was for me. Meanwhile there's all the benefits you can hear and already described.  

Fortunately it turns out the mass makes a great base for springs, and the springs do a great job of erasing the hard edge ringing. I notice a lot of components still on factory feet. If you want to try a nice improvement, Nobsound springs on Amazon are very cost effective. Meantime, good work!