Granite Audio ground Zero #502 Star Grounding System

Unit is like new, box opened, never used. 

The Granite Audio Ground Zero
is an affordable, portable, totally passive, star-grounding system! It
equalizes the ground impedance path of every component in your audio or
video system regardless of the condition of your house wiring and
regardless of how complex your system is. Ground Zero does all this without any connection to the signal path and it’s totally passive! The Ground Zero comes complete with 6 special low impedance cables to connect to
the chassis of each component in your system.  A new feature is a
special Wall Outlet Cable, which can be used to reference the Ground Zero’s ground plane to your home’s ground.*

The Ground Zero can be installed in minutes with
only a Phillips screwdriver. The low-impedance, 32-amp silver switches
do the rest. With a flick of a few switches, your system's noise floor 
is lowered and annoying hum is removed. There’s no need to rewire your
home or use cheater plugs. The Ground Zero is also a great choice for renters: you can have all the benefits of a dedicated ground, but take it with you when you move.

The Star-grounding principle has been around for decades, but Ground Zero
does more: it divides your system into 3 subgroups and allows you to
actually balance the impedance between the groups with 27 switch
settings to get the absolute lowest noise floor and maximize ground loop
elimination. The Ground Zero is the world's first portable, novice-friendly hum elimination device!

Here’s how you use it: The Wall Outlet Cable* connects to any open jack on the back of the Ground Zero
and then connects to any available wall outlet.  Its effect will vary
depending on which jack and wall outlet are used, so test this cable
last.  Connect the rest of the Ground Zero system first
and test the results without the Wall Outlet Cable.  Then see if the
Wall Outlet Cable gives an additional improvement later.

* - Although you don’t have to use it, the Wall Outlet Cable, (a green
tipped cable) allows the Ground Zero to reference your house ground via
the electrical outlet box on the wall.  This may offer additional
lowering of the noise floor, but if you don't get any additional
improvement with the Wall Outlet Cable, then you certainly don't need to
use it. 

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