Speaker Wire Gauges Explained: Which Do You Need?

With most cables and wires, all you need to worry about is how long they are and the connectors they use. With speaker wire, it’s more complicated, which is why we’re taking a look at speaker wire gauges.

How Speakers Carry Sound to Your Speakers

Plugging in a speaker is fairly simple: plug one positive and negative pair of wires into your amplifier or A/V receiver, then plug the other pair into your speaker. What is actually happening to carry the sound of the music you’re listening to from your source to your ears is more complicated.

The signal running through the wires is electricity. Specifically, it’s an electrical representation of the wave form of whatever you may be listening to.

The wires carry this electrical audio signal to the speaker. Here, the electromagnet at the back of the speaker converts the sound back into vibrations that carry the sound through the air and to your ears.

Since this is an electrical signal we’re talking about, the conductivity of the wire matters. This is precisely why the thickness of the wire, or the gauge, matters.

Why We Need Different Speaker Wire Gauges

There’s a common analogy when it comes to electricity that relates it to water. For our purposes, you can think of voltage as the water pressure and resistance as a pipe the water flows through. The narrower the pipe, the higher the resistance.

As wire is conductive, this means it also has resistance. The longer a wire, the more resistance it has, measured in Ohms. That said, a wider or thicker speaker wire decreases resistance, much as a larger pipe would allow more water to flow.

Audio signals use alternating current (AC) instead of direct current (DC), so we’re dealing with impedance (also measured in Ohms) rather than resistance. That said, the basic principles are the same: a thicker wire makes it easier for the signal to flow.

If you’re using too thin a speaker wire, some of the signal will still make it to your speakers, but not all of it. This results in a drop in sound quality and overall volume.

When it comes to speaker wire thickness, you quickly hit a point of diminishing returns. That means there’s little point to choosing the thickest possible wires every time.

How Speaker Wire Gauges Are Measured

So, now we know not all speaker wires are created equally, but why are we talking about them in terms of gauges?

If you’re buying speakers, you’ll notice they often don’t come with speaker cables. When shopping for speaker cables, you’ll see them listed with various figures like 16 AWG or 18 AWG.

Here, AWG stands for American Wire Gauge. As the name implies, this is a standardized system used to measure the diameter of all types of wires. This isn’t a new system, either; it’s been in use since the 1800s.

The system is relatively straightforward, but there is one important thing to remember. Smaller numbers mean thicker wire, so 12 AWG speaker wire is significantly thicker than 18 AWG speaker wire.

Choosing the Right Speaker Wire Gauge

How do you choose the right cables for setting up your home theater or stereo system? It’s actually pretty simple.

For all this talk about thicker cables being better, you don’t need to overthink it. Unless you’re dealing with cable runs of 100 feet or more, you’ll be fine with 16 AWG speaker wire.

16 AWG Gauge Speaker Wire

Most of us never come anywhere near that close, so thinner wire like 18 AWG may be fine. Still, if you’re in doubt, 16 AWG speaker wire remains a great choice, and it should have no problem fitting into the jacks on most consumer amplifiers and speakers.

If you are dealing with 100 feet or longer cable runs, you’ll likely want to step up to 14 AWG or even 12 AWG speaker wire. This is also true if you’re an audiophile with high-end, low-impedance speakers, as these may benefit from the thicker wire.

The only major downside to thicker speaker cable is price. The thicker a cable it is, the more material it uses, and the more expensive it is. This isn’t much of an issue between 18 AWG and 16 AWG wire, but you’ll find the price goes up quickly with thicker options.

For a final tip, audiophiles often obsess over minor details, such as matching cable lengths between speakers. In most cases, you won’t ever hear a difference between different cable lengths. However, you’re more likely to hear a mismatch in cable thickness, so try to run the same length for each speaker in your system.