How to Wire Speakers: A Practical Guide

Wiring speakers comes down to three things: getting polarity right, choosing between series and parallel, and knowing the load that leaves the amplifier at the end of it.

Every passive speaker has two terminals — positive and negative. A speaker cable carries the amplifier's output to those terminals. Get the basics right and wiring is simple; get polarity or the total load wrong and you either lose bass or stress your amplifier.

Polarity and why it matters

Connect the amplifier's positive terminal to the speaker's positive, and negative to negative. When two speakers are wired the same way, their cones move together — they are in phase.

Reverse one speaker and it moves opposite to the other. Where their sound overlaps, the two cancel — bass thins out and the image feels vague. This is the single most common wiring mistake, and it makes no sound of its own, so it is easy to miss.

One speaker, one amplifier

The simplest case: a single speaker presents its own impedance to the amplifier. An 8Ω speaker is an 8Ω load.

Wiring in parallel

In parallel, every speaker's positive connects to the amplifier's positive and every negative to its negative. Parallel wiring lowers the total impedance — two identical speakers halve it.

Wiring in series

In series, speakers are chained end to end: the amplifier's positive feeds the first speaker, its negative feeds the next speaker's positive, and so on back to the amplifier. Series wiring raises the total impedance — two identical speakers double it.

Where to go next

• Compare the two methods in series vs. parallel speaker wiring.
• Work out any combination with how to calculate speaker impedance and its calculator.
• Understand what the amplifier sees in how speaker impedance works.