What is a reference ground?
Updated: Jul 13, 2020
Hello, In my amp kits I include a few extra parts that you will not see in other amp kits on the market. One of these is a wire I call a reference ground. I realize most have not heard of this before so I wanted to explain what a reference ground is and why you need it. One of the most common issues people get with installing their new amp is hearing noise in the system. Alternator whine, sometimes caused by a ground loop. Running a reference ground wire with your rca and remote turn on lead will help protect against ground loops. A ground loop happens when the amplifier and the headunit have different ground potentials (strengths). Electricity always tries to travel the path of least resistance. Sometimes if you do an incredible job grounding your amp (using my grounding bolts that come with the amp kits), and if the headunit is grounding through factory wiring inside the dash that sometimes is not the best ground, it can see a better ground on the other end of the rcas that are connected to the amp. The headunit will try to ground through the factory wiring and sometimes if the amplifiers ground appears better electrically, the headunit can try to ground through that as well. It will try to pull grounds from all the ground sources. By grounding through the RCAs shielding it will create a small amount of DC current traveling right along side the AC signal of the music. This is a ground loop and this is what you sometimes hear. So the theory I was taught, and am reteaching here, is to run a reference ground wire when you run your remote turn on and RCAs. A reference ground does not replace your headunit ground, but it instead connects the headunits ground to the amps ground. So just like you hook the remote turn on from the headunit to the amps terminal, run a reference ground (I include an extra wire for this in all wiring kits except the basic) to tie the headunit ground to the amps ground. By adding the reference ground you are making a new wire that is the path of least resistance. And this theoretically will alleviate some of the grounding potential through the RCAs which will decrease the likelihood that you will get a ground loop through the RCA. Remember, electricity always prefers the path of least resistance, and the reference ground should be less resistance than the RCA shielding. It is such a simple and inexpensive concept, an easy and effective way to protect against getting a ground loop in your amp install.
*The raptor cca amp kits and basic line of amp kits do not come with a reference ground wire. You can purchase the reference ground wire separately at this link: https://www.franksaudiomotive.com/product-page/16g-black-primary-wire Thank you for taking the time to let me explain this. You can find my amp #FAM amp kits here: https://www.franksaudiomotive.com/amplifiers-wiring?Collection=Amp%20Kits