How to Use 4-Ohm Speakers on an 8-Ohm Speaker System

Typical 8-ohm speaker system.

Using 4-ohm speakers in an 8-ohm speaker system is possible if you add a 4-ohm resistor in series with the 4-ohm speaker, or by adding a second 4-ohm speaker in series with the initial speaker. The objective is to keep the total impedance as close to 8 ohms as possible. This ensures maximum power transmission between the speakers and the receiver or amplifier. Adding the second speaker is the best option, because most of the power gets used by the speakers and not lost as heat in the resistor.

Difficulty:

Moderate

Instructions

Things You'll Need

• Speaker wire
• Wire strippers
• Wire cutters

1. Locate the positive and negative feed wires from the receiver or amplifier. Connect the negative feed line to the negative terminal of 4-ohm speaker No. 1.

2. Connect the positive terminal of 4-ohm speaker No. 1 to the negative terminal of 4-ohm speaker No. 2.

3. Connect the positive terminal of 4-ohm speaker No. 2 to the positive feed wire from the receiver or amplifier.

References

• Joe's Tech Notes: Common Speaker Wiring Topologies