[Puma Cat]

Originally Posted by PHC1

The floor.... The floor is the "common collecting ground" for all vibrations. Analogy is thinking in terms of electrical applications.

Vibrations are bad. This is the common belief and many theories and practice in audio hobby focus on that. We spike our speakers so that the cabinet vibrations can be drained away into the "ground" or the floor". Macro and micro vibrations of the speaker cabinet are typically considered bad because they smear the focus of imaging and otherwise "color" the sound. Sometimes, the vibration is said to be sympathetic and is actually a part of speaker design to various degrees of success...

Further, we set up our equipment on racks, often also spiked because the sound waves emanating from loudspeakers will set all objects in motion at their resonant frequency. That much is a given. Some like to use the "feet or footers or coupling or vibration draining devices" between the rack shelves and components.

Obviously different materials have different resonant frequency and so do coupling devices in terms of the frequency bandwidth they either "absorb" or "conduct" away from the vibrating object of interest.

There is probably not one device that can effectively drain or absorb all the frequencies present in the sound wave bandwidth our speakers are putting out. The best devices at doing at such a task are the "active" devices such as the anti-vibration, active tables for precision instruments which "actively" cancel vibrations present in a device of interest. Precision devices such as an scanning electron microscope where vibration free environment is mandatory would be almost useless if it was vibrating.

The only true way to get rid of vibration is "actively". "Active vibration control is the active application of force in an equal and opposite fashion to the forces imposed by external vibration. With this application, a precision industrial process can be maintained on a platform essentially vibration-free."

Other than active vibration control, everything else is "tuning" for a specific bandwidth since there is hardly a material that would absorb or dissipate a very wide range of frequencies.

Getting back to our "floor" or "grounding". Obviously a slab of concrete under the carpet is very different than a hardwood floor supported by joists on the other floors of the house. Two different materials, different vibration draining/absorbing coefficients. Walk on a slab of concrete, zero vibration. Walk on a wood floor supported by joists, vibration. That doesn't mean concrete doesn't vibrate, it does, just at a much higher external force and frequency of resonance. But as we all know, even bridges collapse from resonant frequencies as witnessed before.


Mass is obviously our friend when it comes to audio. The thickness and material selection for the chassis build is also pretty important. Some manufacturers will take that into account, some may not. <SNIP>

Roy Gandy of REGA would disagree with you on that one, Serge!

At least when it comes to turntables...