Speaker Wire Gauge: What Gauge Wire for Your Speakers?

The gauge of a speaker wire refers to the thickness of the cable. The larger the diameter, the lower the gauge number.

But the big problem is knowing what size to buy. Will a thick speaker cable sound better? Or can you buy some cheap, thin stuff without worrying? Let’s find out.

Speaker Wire Gauge Types

The American Wire Gauge (AWG) is the standard used in North America.

This standard wasn’t created explicitly for speaker wire but is used in various industries that employ different wire types.

You might also hear it called the Brown & Sharpe wire gauge.

Although the AWG specifies a wide range of sizes for different uses, the most common gauges for speaker wire are probably 12, 14, and 16.

However, thinner 20 or 22 AWG is more common in budget systems that come with wires.

Any of these options will work great for most wiring needs in a regular home theater or music setup, but there are ways to narrow down the best gauge for your room, which I’ll get to in a second.

Is the AWG standard recognized around the world? Unfortunately not; there are several other wire gauge standards used worldwide.

Here is a wire gauge comparison chart that might be useful for comparing other wire sizes, including Standard Wire Gauge (SWG), Washburn & Moen (W & M) and Birmingham Wire Gauge (BWG).

In the UK, speaker wire is often measured by cross-sectional area in square millimeters (which is not the same as the diameter).

However, sometimes, the AWG is quoted. How confusing is that?

Here is a chart that shows the comparison of the most common AWG speaker wire sizes and cross-sectional areas:

The common wire sizes for speaker systems in the UK are:

• 0.5 mm² (roughly 20 AWG)
• 0.75 mm² (about 18 AWG)
• 1.5 mm² (about 16 AWG)
• 2.0 mm² (around 14 AWG)
• 4.0 mm² (roughly 12 AWG)

So, it’s not an exact match to the table above, but you can see the approximate equivalent size in AWG.

The gauge of your speaker wire is the most important feature when deciding what cable to buy.

Why? Because as the wire gets thicker, the resistance decreases. And, to get the best audio performance, you want the resistance below a certain level.

What Is the Best Wire Gauge For a Speaker?

What is the right size speaker wire for your room? Well, it depends on a couple of factors.

The best speaker wire gauge for your setup will depend on the following:

1. the impedance of your speaker
2. how far you want to run the cable
3. the material of the core conductor

Veteran loudspeaker engineer Roger Russell says the ideal resistance for a speaker wire is less than 5% of the rated impedance of the connected speaker.

If so, there will be no audible effect on the sound coming from the amplifier.

So how on earth are you supposed to work that out? Fortunately, Roger has also produced a simple table to make this clear.

Here are his guidelines for any 4, 6, and 8-ohm speaker connected with two-conductor copper wire – which should cover most speakers designed for the home.

Roger also has the numbers for a 2-ohm speaker on his site, so check that out if you need those.

As you can see from the chart, if you have an 8-ohm speaker, even a skinny 22 AWG wire can be run up to 12 feet with no loss of audio fidelity.

That might be plenty for your front left, front right and center speaker.

Not that you should necessarily buy 22 AWG wires – most systems will use 16 or 14-gauge AWS wires. I do, anyway.

16-gauge copper wire can run up to 48 feet with an 8-ohm speaker.

So, if you want a size that suits most circumstances, 16-gauge copper wire is probably a good fit without spending a fortune.

But for a speaker with a lower impedance, or if you plan to run very long cables around the room, you might go with 12 or 14 AWG to be safe.

Even though the table refers to lengths up to 200 feet, you wouldn’t want to run cable this far. Roger suggests a maximum cable run of 50 feet.

What About CCA Wire?

You shouldn’t forget that this data refers to copper speaker wire. If you buy copper-clad aluminum (CCA) wire, this will have an increased impedance compared to copper.

Roger Russell doesn’t provide these figures but bear this in mind when buying your cable. As a rough rule of thumb, maybe get the next thickness up to be on the safe side.

So, if 16-gauge copper wire is fine for your room, maybe get 14-gauge if you buy CCA. Of course, this may eliminate the cost savings of buying CCA instead of copper! Life is full of tough decisions.

It really doesn’t matter which you buy for short cable runs – say 10 feet and under – you are unlikely to hear a difference.

If in doubt, and assuming you can afford it, buy copper cable.

• Learn more: Speaker wire guide: all you need to know

What Is Bigger – 14 or 16 Gauge Speaker Wire?

14-gauge speaker wire is thicker than 16-gauge. 14-gauge wire is 1.6mm in diameter, and 16-gauge wire is 1.3mm.

Are Thicker AWG Speaker Cables Better?

In some circumstances, thicker gauge wire is better, but it won’t make much difference in most cases. A thicker gauge wire will have less resistance (impedance) – and less resistance is good.

If the resistance is kept below a certain level in your system, it won’t degrade the audio passing from your amplifier to your speaker.

So, if you need long cable runs, it is more important to use thicker wire to keep the resistance low.

However, it isn’t the case that thicker wire is better or worse – it’s about getting the correct gauge for the job.

Depending on the length of the speaker wire that you need, a thinner speaker cable may have the same audio performance as a thicker one.

But a thicker speaker wire might be better if you need to run a cable for a longer distance.

What Gauge Speaker Wire for Home Theater and Surround Sound?

Choosing the correct wire gauge might seem necessary for high-end stereo audio speaker systems.

But what about home theater and surround sound? What is the correct wire gauge for this?

Well, the rules are the same – you are still using an amplifier, speaker and wire. So, select the correct gauge depending on your speaker impedance and cable length.

If you want a quick answer, a 14-gauge AWS speaker wire should cover most solutions with no problems – and most people will be fine with the cheaper 16-gauge AWS.

But, if you want to be sure, look at the speaker cable gauge chart above and make the right decision for your room.

If Your Speaker Has 8-ohm Average Impedance, Which Gauge Wire Should You Buy?

Great question! I said previously that the wire gauge you buy depends on the impedance of your speaker.

However, a speaker’s impedance is nominal, which means it is an average value. So, it can go above and below the nominal figure at some frequencies.

If so, how do you work out the best wire size?

First, you should find out the minimum impedance for your speaker – you should be able to get this from the user manual or the manufacturer’s website.

Then, if you wanted to be sure of getting it exactly right, you could use this as the correct impedance.

Now, you have plenty of slack when working out the best wire gauge for a cable length – so the chances are it won’t make a difference.

But, if you are close to the distance limit for a particular gauge, you might want to consider the minimum impedance of the speaker rather than the nominal value.

Either that or get the next size up anyway.

Should You Install Expensive Speaker Wires for Your Front Speakers and Cheap Cabling for the Surrounds?

This is a common way of thinking. In the past, before I knew better, I’d do it myself.

The idea is that thick, expensive wire is better quality, so you should use this on the most important speakers at the front.

Whereas a surround speaker is less critical – and further away – so you can save some money and buy cheaper, thin speaker wire. The funny thing is, the opposite is true.

The thicker wire has less resistance, so it should be used for longer wire runs. For shorter runs, you can get away with much thinner wire.

In the end, don’t overthink this.

If your maximum cable run is less than 48 feet – and you have an 8-ohm speaker – just buy a 16-gauge copper wire and use it for everything.

• Learn more: How to connect wires to your speakers

About The Author

Paul started the Home Cinema Guide to help less-experienced users get the most out of today's audio-visual technology. He has been a sound, lighting and audio-visual engineer for around 20 years. At home, he has spent more time than is probably healthy installing, configuring, testing, de-rigging, fixing, tweaking, re-installing again (and sometimes using) various pieces of hi-fi and home cinema equipment. You can find out more here.