Review on Enhanced Noise Filter B25N: BOSS Audio Systems Ground Loop Isolator for Optimal Car Audio Performance by Alexander Craner

So first of all, anyone who claims that they can catch fire or generate a 5-volt drop is ignorant. This is for the signal. It varies between 1.2 and 4 volts. Claims that it can't handle high current are silly. The current in the signal is negligible. These are two transformers with the same winding and RCA cables for signal, not speaker level. fractions of watts. It isolates well if your problem is a ground potential difference causing one element to be grounded through the other through the signal wire. There are some losses, but that always happens with the transformer. The case is plastic with fake cooling fins, which is silly as there should never be enough heat in a device of this nature. This works well as expected, but only for a specific problem. In my truck, the amps are grounded to the chassis and the main unit is grounded through the wire harness. There's a non-permanent difference that I couldn't isolate even after adding a chassis ground to both ends, so the problem was resolved.