Grounding with a Earth box?


OK so help be understand something.   I understand the value of grounding equipment, but what is the value of having a woodbox with salt, earth, minerals etc  do for grounding?  How is supposed to work or be better?


brubin
Puritan has a unique approach to extra grounding.
http://www.puritanaudiolabs.com/products/ground-master/
Despite possible appearances to the contrary, whatever they are doing passes all the British safety code electrical standards.
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Odds are @twoleftears , it is just Y-capacitors connecting the two terminals together.  They are a type of capacitor that fails "safe" ... i.e. it does not form a short, but stays being a capacitor.

Someone with a grounding box:  What is the voltage differential measured between the grounding box and the "D" hole, the safety ground on a wall outlet?  Curious to see if a voltage can be seen between the grounding box and the earth ground of your home.