Jim Weil, the designer of Sound Application, has worked extensively over the years to try to limit the effects of mechanical resonances on his passive line conditioners and he is never fully satisfied with their immunity. This is a testimony to the fact that passive plc's sitting on the floor are subject to micro-shaking, resulting ultimately in some smearing of the audio signal. Whether isolation devices help more than they hurt is another question; I've never found external treatments to be overly helpful.
A related comment - I've often found the passive network boxes on networked cables to be quite vibration sensitive. Setting them directly on the shelf of a rack has resulted in very audible smearing, which is eliminated by hanging them or attaching them to the wall.
This is a subject I would really like to understand - and don't.
I continue to disagree with Stehno. Floorborne vibration is a far bigger problem, especially on raised hardwood floors, than airborne. The surface area of a network box for airborne interactions is small.
A related comment - I've often found the passive network boxes on networked cables to be quite vibration sensitive. Setting them directly on the shelf of a rack has resulted in very audible smearing, which is eliminated by hanging them or attaching them to the wall.
This is a subject I would really like to understand - and don't.
I continue to disagree with Stehno. Floorborne vibration is a far bigger problem, especially on raised hardwood floors, than airborne. The surface area of a network box for airborne interactions is small.