What is a dual voice coil subwoofer and how do you wire it?

All you really need to know is that a dual voice coil has two sets of terminals, this gives you added flexibility when connecting a subwoofer to an amplifier. Speaker resistance is much more complex, more on that below. But for now the goal is to match the nominal impedance of your subwoofer (or subwoofers) to your amplifier. Here is a schematic to show the difference between single and dual voice coil subwoofers.

Here is a picture of a pair of dual voice coil subwoofers, the terminal pairs are circled in red. There are two pairs on each subwoofer. In this case the voice coils are wired in series. For more on this scroll to the bottom of the page for some sample wire diagrams.

Here are some schematics showing the two ways that you can wire up a dual voice coil subwoofer.

Here is an example of a single voice coil subwoofer. It has just one set of terminals.

Here are some schematics demonstrating series vs parallel for a single voice coil subwoofer.

Subwoofer Ohms (Series-Parallel) Calculator

With the above information you should know enough to use this calculator, additional wire diagrams are included below. One caveat, this calculator will not let you mix impedances or numbers of voice coils. It assumes that you are working with matching subwoofers.

Subwoofer Resistance Calculator

Select Voice Coil Resistance (Ohms):

Select Number of Voice Coils:

Select Coil Configuration:

Number of Subwoofers:

Select Subwoofer Configuration:

Now I am going to break your brain!

In this picture I am measuring a 4 Ohm voice coil and it is not 4 ohms!

That is because subwoofer impedance is actually a lot more complex. I explain some of that in this video:

As you can imagine there is a near infinite number of possible wire configurations. Here are some examples to help you get started wiring up your own system.