Operating instructions

3-2a) GROUNDING OVERVIEW
An audio installation is only as good (or bad ) as its grounding system. Poor grounding practices are the number one cause of RF
interference, hum, crosstalk and noise.
Grounding is used for FOUR distinct and different purposes:
(1) SAFETY FROM SHOCK HAZARD
(2) SHIELDING FROM RF INTERFERENCE
(3) AC POWER DISTRIBUTION
(4) REFERENCING BETWEEN TWO OR MORE PIECES OF ELECTRONIC EQUIPMENT (ELECTRONIC GROUND)
These four purposes are often at odds with each other and therefore require separate grounding systems. As an example, AC power
ground carries large current and creates transients as equipment is turned on and off. It is therefore not a clean ground and should not
be used for or connected to Electronic Ground where it will induce noise. As another example, RF ground should drain RF energy
away from electronic semiconductor devices AND Electronic Ground where the RF can be reintroduced into the equipment. A
last example is Shock Hazard ground (Chassis ground) which is AC ground from the third prong of the AC power plug. This ground
is normally connected to the metal chassis of the electronic product to prevent shock hazard. If this ground is connected to Electronic
Ground and an unbalanced signal wire is used (it will have Electronic Ground also), then there are two different ground paths and a ground
loop is created with its associated 60 cycle hummmmmm. The important point in this discussion is to remember the basic principle that
Electronic Ground must remain pure and NOT connected to (1) Safety Ground (2) RF Ground or (3) AC Power Ground. Star
ground networks are effective in reducing crosstalk and hum.
IMPORTANT --- SMALL STUDIOS CAN BE ASSEMBLED USING SLOPPY GROUNDING
PRACTICES AND OFTEN WORK ACCEPTABLY. HOWEVER, THAT IS SIMPLY LUCK.
GOOD GROUNDING PRACTICES SHOULD ALWAYS BE USED!!!
Star Ground Network
EARTH
GROUND
SINGLE
STAR GROUND
POINT
INDIVIDUAL
GROUND
CONDUCTORS
Arrakis Systems, inc. --- 6604 Powell st., Loveland, CO 80538 --- 970-461-0730 --- www.arrakis-systems.com
INSTALLATION PROCEDURES
GROUNDING 3-2)
3.5