I can’t accommodate a Brain / Brawn stack arrangement so the system has to cope with the vibrational harmonics of the transformers transmitted from lower on the rack.
So, how to mechanically isolate the ‘Brain’ components.
First: rule out solutions based on damping, such as sorbathane.
Second: rule out spring systems as; 1, they’re more difficult to design and build; 2 some of the boxed have vary asymmetric weight distributions.
So, think about using the properties of systems based on dissimilar materials… Well to avoid transmitting vibration we have to limit the energy transfer; this can be my absorption, compliant suspension or reflection. I’ve rules out the first two, so use reflection.
Across an interface, if the propagation velocity of a wave is different in each medium the refection from the interface is increased.
One surface is glass, so we need something that has a higher sound velocity or a lower sound velocity, but is still rigid (rather than compliant). Now this could be mild steel, which has a lower sound velocity, but is heavy, or try silicon nitride which has a significantly higher sound velocity.
Silicon nitride, because silicon nitride is so much lighter it can store less energy, so select silicon nitride.
Next is what to put underneath, again use something with a very different sound velocity but is still rigid. Brass has a lower sound velocity than steel (and tends to have good acoustic properties anyway) so a brass lower plate it is.
All we have to do then is keep the ball in place…
So much for the theory
And in practice…
It works!
There’s a bit less background ‘clutter’ in the sound, but more significantly it organises all the elements in signal in a much more coherent manner.
