Herbies Pucks floor spike protectors...

In regard to JTCF's post above: I temporally used 8M carriage bolts with my Focal 726-floor standing speakers (two months) while I waited to receive my custom 8M spikes. As soon as I installed the spikes I noticed an immediate improvement with dynamics, sound stage, and bass. I believe you don't know what works until you try it.

I still have some gliders. They didn’t do much for me under equipment rack nor Sound Anchors for my speakers (laminate floor), but they protect the flooring fine :D

Put Herbie's giant pucks under spikes of Legacy Signature SE on suspended hardwood (parquet) floor. Sound appears more open than when on rubber feet, though this is preliminary and more positioning experiments are needed. Fortunately the pucks allow this to be done with no more effort than using frosted silicone mats, which looked a bit strange. On on the other hand, given Legacy's inexplicable indentation of the feet from the speaker corners, the flared Herbies produce the visual effect of refined cabinetry on silly little duck feet, ready to waddle off at any moment. Final judgment reserved until one of my candid and witty friends gets a hard look at this setup. (Herbie wanted a photo, but I can't upload to their response form).

I put the Herbies Gliders under my Vandersteens....they absolutely ruined the sound....returned them.  Herbie was very nice about it....