Compatibility of Car Audio Components

When choosing car audio components, it is important to ensure that the components you are purchasing are compatible with each other. 

The big point here is the subwoofer/amplifier compatibility. Each subwoofer has an Ohm rating (resistance). This is the rating that will tell you if any given subwoofer will work with the amplifier.

We will look at single voice coil subwoofers first. Subwoofers with single voice coils have ratings from 2 ohm up to 8 ohms. Your amplifier will be stable 4 ohms or lower... this is important spec as well!

Say for instance we have two 4 ohm subwoofers. Here are a couple diagrams that will tell us what the final impedance (ohm rating) would be.

With that, we now know the top configuration would work with an amplifier that is stable with a two ohm load attached to it. If the amplifier is only stable to 4 ohms, this configuration could harm your amplifier!

Say for instance we have four 4 ohm subwoofers. Here are a couple diagrams that will tell us what the final impedance would be.

Given those impedance loads, we know with the first configuration, we would need an amplifier that could handle a 1 ohm load. Putting a heavier load (1/2 ohm) could result in a fire!!

Next we will look at dual voice coil subwoofer configurations. The dual voice coil (DVC) of these subwoofers will expand your possibilities as far as the impedance of your system goes. 

Say for instance we have two dual voice coil subs that have an impedance of 2 ohms. Here are some wiring diagrams

As you can see, with two dual voice coil subwoofers, we can achieve a load of either .5 ohms, 2 ohms, or 8 ohms. This expands your choices of amplifiers and what will work with your subwoofers. 

As always, if you are unsure, please check with your car audio dealer. Most will give advise free of charge!!