High quality balanced signals can help deliver signals with high levels of audio fidelity in spite of the harsh and noisy electromagnetic automobile environment. Current balanced signal handling methods offer additional advantages including the enhancement of the signal cable. Power cables too can benefit from current balancing, and unlike signal cables, no special electronics are required.

One advantages of current balancing is that it cancels wire self inductance which can be a significant impediment to the delivery of power in spite of adequately sized power wires. Current balanced power wiring offers many of the same advantages that stiffening capacitors do when adequately sized wires are used.

Another advantage of current balancing is that it eliminates most of the magnetic fields due to the currents in the wire that would otherwise contribute to the induction of engine noise, alternator whine, and feedback distortion in signal cables. This effect is illustrated in figure 1. This fact makes it possible to wire curent balanced power cables and signal cables together. When all cables follow the same paths together this way, other interference noises they are subject to will be rejected. This works because all conductors will be subject to the same magnetic fields along the same paths, and they will cancel as the amplifier ground reference tracks the interferences in the signal cables. You might call this the theory of relativity applied to audio signal cabling — interference noises are cancelled because there is no interference relatively speaking between the amplifier input and its ground.

Only two wiring practices need to be observed, and no special equipment is required to deliver power with current balancing: First, the ground connection and the power connection of the amplifier must follow identical paths from the battery, and Second, it is important to be sure that there are no other paths for power current to flow except by way of those two power connections. In other words, every amplifier power and ground wire should be routed together, and be sure that the vehicle chassis does not drain any ground current through any possible shorts between the body of the vehicle and the amplifier enclosure or ground wiring.