There are 2 main issues that isolation devices may solve.
#1 is external vibration to the component (e.g., footfalls causing a record to skip)
If you have a solid floor and solid rack/stand, and footfalls are a non-issue, this should be easy to solve and not involve tire tubes and sand boxes. (I have zero footfall issues so my solution is designed around that scenario)
#2 is internal vibration generated by the component (integrated tube amps and CD transports are among the worst offenders)
#2 is addressed by coupling the component to allow the vibrations to dissipate and absorbed by something that can convert that energy into heat. In this case, sorbothane, wood etc. makes it worse. In my case this simply meant removing the plastic "buttons" on the bottom of the metal turntable feet and removing the stock rubber/plastic feet from my amp, then applying several different application-specific solutions from Symposium. They are reasonably priced and they work. Peter knows his stuff.
Details are in my virtual system in case your are interested.
The biggest impact was my integrated tube amp, followed by the center channel speaker. (not listed in my system but I use JR. roller blocks to lift the Paradigm speaker off the wood cabinet instead of having it sit on stock rubber feet, or sorbothane pucks, and the clarity and detail improved - a LOT), then TT.