Should I use Speaker Spike / Isolation Base or Something?

I am another in favor of the ISO Acoustics. I use the GAIA II and the carpet spikes. Huge improvement on focus and bass articulation.  

I tried all kinds of things....nothing was better than the spikes I have...many a definite reduced performance.  I'm lucking in that my speakers on their spikes, are on ceramic tile, that are cemented to the foundation of the house.

stringreens         +1 +1 +1

stereo5     Why not try with just the spikes?

It all depends on the floor and the speakers. There is a setup man who wrote a great article on why he never uses spikes and why. I had Quad speakers and adding spikes turned them into unlistenable, my current open baffle speakers sound soooo much better with no spikes and just using the feet that the spikes screw into on each speaker. Yes, with spikes it does sound clear and clean, but the body, weight, dynamics are reduced, vocals airy but no chest of weight to it. So much is generalized and becomes something you just do, I have learned over 30 years to think outside the box and try something and see how it works in your system, and #1 your room acoustics impacts more than any power cable, interconnects or a gear change, room focus to me must be #1, spikes, no spikes try it for yourself and listen. My. Dynaudio Confidence 5 speakers sound good with spikes so there you go.

You want to couple the speakers to the floor.
IsoAcoistics will decouple as will any soft things like springs.
For a night and day improvement go with Stillpoints Ultra Minis. They screw into the speaker.
They will couple and turn the vibration to heat. But the movement of the drivers will stay in the box and not be drained into the floor.
You will need 6 x $100. They will be $25 less each since you don’t need the bases. I have them on my 190 lb speakers and the effect is transformative. The best $600 you can spend.