How to Make Series Connections

In short, a series connection is based on connecting the positive terminal of one component to the negative terminal of the next. This applies both to batteries where the voltage increases according to the number of units, commonly used in high-voltage (HV) systems and to identical speakers, where the resulting impedance can be up to double the nominal impedance. Below are examples of how series connections can be made between speakers.

Example 1:
In this example, we have a pair of 2-ohm speakers to be connected in series to a 4-ohm amplifier. We can use a simple multiplication formula to determine the resulting impedance of the series connection:

Speaker impedance × number of speakers = resulting impedance.

So: 2 Ohms × 2 speakers = 4 Ohms

The image below illustrates how this connection would be made in practice, showing that the remaining wires are connected to the amplifier output:

Following the same logic, we can also apply a series connection to dual voice coil speakers. The calculation would be as shown below, followed by an illustration of this connection (remember that the remaining wires should be connected to the amplifier output).

Speaker impedance × number of speakers = resulting impedance.

So: 2 Ohms (impedance of each speaker coil) × 2 (total number of coils in the dual setup) = 4 Ohms (final impedance)

Another example would be a single dual 4-ohm voice coil speaker, resulting in a final impedance of 8 Ohms.

In conclusion, we can see that series connections of speakers are generally used in systems where a higher impedance is required, in order to achieve the desired results.