Speaker vibration isolation

Blu Tack between my suspended wood floors and my Infinity RS1b mid/high tower feet. Reasonably priced and works well. 

here's an objective test some people may find valuable, though it is for studio monitors rather than floor standing speakers.

My guess would be that floor standing speakers have even more weight (to driver ratio) and less vibration.

http://ethanwiner.com/speaker_isolation.htm

I did listen to a demonstration of Focal speakers with and without isolation products applied at Rocky Mountain audio Fest in Denver Colorado (2018). The isolation product was impressive, in that it seems to clear up the vocals, but it also raised the speaker a couple of inches, which means that the Tweeter was in a different position, which could lead to the same effect.

Just wanted to add my experience to those who have found a significant benefit when adding Gaia's to speakers formerly spiked to a concrete slab.  I have no explanation or technical expertise, but the improvement in image clarity was not small and (to me) well worth the cost.

My Klipsch Heresy IIIs must have pretty low center of gravity buy I don't take 'em out on the road much to see how they corner, and when I used Vibrapods with a higher center of gravity "tower" speaker they worked great with those also...'pods are omni directional...obviously...if they're too inexpensive for some I get that...enjoy uber expensive whatever ya want, but keep yer grubby hands off my 'pods!

Boenicke speakers employ a unique swing base isolation system. They are hung on stainless steel cables at the back and rest on a ceramic ball in cups at the front. They work really well and contribute to the clarity of these speakers.