I had a dealer subcontract a bespoke custom made glass shelves stand to incorporate the same principles as a NAIM FRAIM
The tempered glass shelves resonate differently depending which side you tap on. The audible differences are there and not subtle for proper placement purposes
Then the glass shelf rests on machined ball bearings wherein the rack has a shallow “ dimple” depression in each corner for the ball bearing to actually sit in
From the NAIM FRAIM commentary on the NAIM website:
https://www.naimaudio.com/product/fraim-0
“... Our Fraim equipment support system has been carefully designed to provide the perfect platform for Naim Audio electronics to shine. Each level is carefully isolated from the next using a cup-and-cone interface. An additional, double-layer base platform provides further isolation from resonance. A toughened glass sub-shelf rests on minimal-contact ball decouplers, providing even more isolation...”
Done properly ..... highly recommended.