Ground loop isolator? How?

Can someone help? I was told to do a ground loop isolator to get ride of some noise on a radio install. Are they just telling me to move the ground to a better location? Thanks!!!

Before you go and spend any hard earned $$$ on a ground loop isolator. Please ensure the following things are done, and varified in your current installation. A) The HU (head unit) is well grounded to a large mass of the vehicles chassis frame, using a bolt and star washer. Simply attaching the ground lead wire from the HU to a tube frame does not ensure a low (resistive ground plane reference.) As the spot weld increases the resistance of the surface it is mated to. Tapping into the actual body frame is a sure thing, as long as the surface is completely clean, and free of paint, and corrosion. B) Ensure that your signal (RCA) cables are well routed seperately and away, from your ground and power wires. This will ensure *induced* EMI is not the cause. C) Ensure that the amplifier(s). Assuming you have them, are grounded with the proper diameter (guage) of of wire to the vehicle chassis with a ring terminal. D) Ensure that all speaker(s) and cross over wires are not in the same path as any other power / EMI producing units, such as the heater blower, etc. E) Ground wires should be a short as possible, using the proper guage to ensure proper current flow, and reduced resistance. F) Varify that your alternators (diode pack) is not bleeding off RFI / EMI. Just because the noise varies with RPM, does not automatically point to a defective alternator (diode pack) which will only produce a half wave rectification. ie, The alternator no longer produces a clean DC voltage to the vehicles power accessories, but spuratic AC and DC, as one of the 8 diodes are shorted out. G) Varify that your *gain* on the amplifier is not in fact turned up too high. H) If the HU or the amplfier has a hi pass / low pass filters / equalizers you will want to ensure that they are not indeed set to amplify the noise your are hearing now. There is alot more to do, and ask... FYI: A ground loop isolator contains an isolation transformer for each channel. The transformers generally have a 1:1 ratio. Which neither boosts nor cuts the audio level. The audio wave form is magnetically coupled through the transformer's core. Since DC can not flow through the transformer, the DC path is cut, and the noise is eliminated, leaving you a clean audio signal to be heard. Regards EVIL Teken

Thanks, that helped alot!!!