A type of grounding scheme used in some studios to prevent ground loops. It requires isolating each piece of gear from AC ground (using a ground lift adapter) and running a separate ground wire from the chassis of each piece (including the racks themselves) back to the main studio ground (we call this “Technical Earth”). This “Tech Earth” gets connected back to a main AC ground, and/or a large copper rod driven 18 feet into the ground. Thus every piece of gear still has AC fault protection, but no earth grounds are tied together. Technically limited ground loops can still exist in the studio signal wiring, but the path length differences are minimized to an extent that it isn’t likely to be a problem. Star Grounding is a time consuming and complex wiring scheme, but is generally very effective at preventing ground loops and works great in conjunction with other measures such as telescoping shields. Occasionally you’ll still find some piece of gear that requires audio transformers to eliminate ground loops. Generally you’ll find that with today’s equipment, you really don’t have to go as far as all this. Telescoping shields, balanced lines, and careful consideration to signal cable wiring with today’s equipment is often good enough.