toddverrone, it's my professional opinion that coupling using spikes, etc would be best on a concrete slab unless there is an extreme source of outside vibration such as heavy road traffic.
I was, for many years, a Field Analyst and multi-plain balance specialist for The Westinghouse Corp. The same principals apply, weather it pertains to high rpm machinery such as turbines or large rotating machinery such as scrubber fans or to audio performance. Frequencies and Cycles are directly related and impact their connective apparatus and structures the same. Aside from out of balance, the major cause of failure or disruption of rotating machinery or any of it's coupled apparatus or connective structure, are resonant frequencies and their harmonics; looseness or wear anywhere in the chain and outside interference. All the same applies with audio and the solutions also the same. Dampening adds mass and can reduce vibration by eliminating the problem of resonance. If there is looseness anywhere in the system including a flimsy cabinet, shaky floors or loose parts it becomes a problem causing vibration and serves to amplify outside sources of vibration. It has been my experience that, when everything else has been addressed, if the floors are very solid and the cabinet/rack and stands are solid - coupling using spikes, etc is very affective. If the floor, cabinets and other structures are not solid or there are outside sources of vibration, then isolation devices would probably work best. Instead of blindly spending allot of money experimenting with what worked in someone else's system, evaluate your own system and structures.
Good luck,
Jim
