When you have a great sound-producing electronic source, such as a television or even an electronic musical instrument, and a great set of speakers, the only thing left is to purchase the right speaker cable. Does cable length affect sound quality? What other variables of a cable can affect sound quality?

Cable length does affect sound quality – the shorter the cable, the better the sound quality. Sound quality is also affected by the thickness of the cable and the wire's material. Thicker cables tend to produce better audio signals.

Throughout this article, you’ll also learn the following information about how the length, shape, and size of a cable affect sound quality:

  • Different uses for speakers and how cables impact their performance
  • Which materials are best for audio transmission
  • Recommendations for speaker cables on the market
  • How you can find the best cable for the task at hand

What Are Speakers Used For?

The purpose of a set of speakers is to amplify sound from a source device. The source device can even be a musical instrument, such as an electric guitar. The more common electronic devices in your home theater setup would be your television or a HTPC (computer).

They are used to amplify sound. This means that when a musical instrument such as an electric guitar is connected to speakers, we would expect it to be louder. This is useful when performing in front of a large room crowd since you would want your music to reach the last person standing at the back of the room.

The same is true when you're watching your favorite show on television. Perhaps you want to achieve a louder sound for a more dramatic, cinematic effect. You might be watching the show in a large living room with a few other family members. You want the sound on your screen to be louder than it would be if you just played it on the television without connecting it to speakers.

So the first objective of the use of speakers is clear. You want the sound to be amplified, and you want more people to participate in listening. The next is you want the sound to be as clear and as similar to the source.

There would be no point in having speakers if the speakers sound distorted. If you were playing an electric piano in a concert, and the sound that came out is in a different key, that would defeat its purpose. I'm really seem to be exploring the musical parallels here. Similarly, you wouldn't enjoy watching a film on your television if the voices of the characters came from the speakers at a different octave.

Therefore, sound quality is key. This objective goes hand in hand with the first objective of sound amplification. We want our speakers to make sound louder and for the sound to be high-quality and similar to the source.

To achieve this, you would, of course, need to purchase good speakers. Suppose you spent good money to purchase great speakers. Are there any other factors that can affect sound quality? Yes, the cable you choose to connect them with can also affect sound quality.

How Do Speaker Cables Affect Sound Quality?

The role of a speaker cable is obvious: to connect the source device to the speakers successfully.

Speaker cables allow the transmission of electrical signals from the source device to the speakers. For example, the cable's role is to allow transmission of electrical signals from your musical instrument to the speakers, so that a complete connection is made and music is transmitted and amplified in volume.

Of course, speaker cables do this in varying degrees of effectiveness. The more effective a speaker cable is, the better it allows electrical signals to be transmitted. This, in turn, produces a high-quality sound.

Two main factors affect a speaker cable's ability to effectively transmit electrical signals: the length of the cable and its thickness. To understand why this is the case, we need to turn to physics for answers.

The movement of electrical current through a cable obeys the laws of physics. There is a physics law – Ohm's Law – that codifies how effectively a cable can transmit electrical current. Let's look at a variation of Ohm's Law to understand how cable length and thickness can affect its effectiveness.

A variation of Ohm's Law states that the electrical resistance in a cable is directly proportional to the cable length and inversely proportional to the cable thickness. This can be simplified into a formula, which is R ∝ L/A, where R means Resistance, L means Cable length, and A mean cross-sectional area of the cable, or otherwise known as the cable thickness.

Electrical resistance is the opposite of electrical flow in an electrical circuit. In other words, the electrical resistance prevents a cable from effectively transmitting electrical signals from the source device to the speakers.

To ensure that sound quality is maximized, the goal is to reduce electrical resistance in a cable. The lower the electrical resistance encountered in a cable, the higher the sound quality on the other end.

What factors are in play that can affect electrical resistance?

The Length of the Cable

The first is the length of the cable. Since electrical resistance is directly proportional to cable length, the longer the cable, the greater the electrical resistance, and the greater the electrical resistance, the lower the sound quality.

This addresses the primary question of this article. The longer the cable length, the lower the sound quality. Inversely, the shorter the cable length, the higher the sound quality, provided all other variables remain equal.

The Thickness of the Cable

Let's go a step further. The physics formula mentioned earlier also states that electrical resistance is inversely proportional to the cable thickness. This means that aside from cable length, the cable's thickness also affects the transmission of electrical current from the source device to the speakers. Therefore, it is a factor in the quality of sound output.

Inversely proportional means that when the value of one variable increases, the value of the other decreases. In this case, it means that the thicker the cable, the lesser the electrical resistance, and the lesser the electrical resistance, the higher the sound quality. In other words, the thicker the cable, the higher the sound quality, assuming that all other variables are kept equal.

How to Choose the Best Cable Based on Length and Thickness

By understanding the laws of physics governing the transmission of electrical current through a cable, we can accurately make decisions regarding the best type of cable to purchase for the best sound quality.

As for cable length, the shorter the cable, the lesser the electrical resistance, and the lesser the electrical resistance, the better the sound quality. This means that your ideal cable length should be as short as possible.

You can make a decision when presented with a choice of two cables with differing lengths. Between a 10-foot cable and 50-foot cable, which one would produce the best sound quality? The answer is the 10-foot cable, assuming that all other variables are the same.

However, the shortest cable might not necessarily be the most practical. This is especially true if your source device and your speakers are situated far apart and there is nothing you can do about it. This could be due to the arrangement of furniture in the room or its layout. Whatever the case, sometimes purchasing the shortest cable in the store is simply not possible.

Therefore, the best cable length is the shortest length possible that is still practical, considering the distance of your source device from your speakers. If your source device's distance such as your television from your speakers is 10 feet, then the best cable length for you would be 10 feet long, or slightly more to give it some leeway. If the distance is 20 feet, your cable length should be at least 20 feet.

Do Speaker Cables Need to Be the Same Length?

Speaker cables do need to be kept as short as possible, but it is not necessary to have cable lengths equal to each other. The only time this usually makes a difference is where the cable length differences are at least 5:1 of identical wire gauge.

I also like this video on the subject:

What Happens if Speaker Cables Are Too Long?

Obviously you need long cables to be able to connect speakers from longer distances, but what is too long? This initially depends on your amplifier, your speakers, and the wire itself.

A longer cable will increase the resistance between your amp and speaker, which will ultimately affect the amp's damping factor. This will lead to modulation distortions, losing some highs and have a more loose bottom end. In short, you will be able to hear the difference.

You can mitigate the problem by using thicker cables. See this handy chart below to get an idea on max speaker length by cable thickness:

Speaker Wire Gauge4 Ohm Speaker6 Ohm Speaker8 Ohm Speaker
24 AWG3 Feet5 Feet7 Feet
22 AWG6 Feet9 Feet12 Feet
20 AWG10 Feet15 Feet20 Feet
18 AWG16 Feet24 Feet32 Feet
16 AWG24 Feet36 Feet48 Feet
14 AWG40 Feet60 Feet80 Feet
12 AWG60 Feet90 Feet120 Feet
10 AWG100 Feet150 Feet200 Feet
Speaker wire gauge is in AWG. Speaker cable length is in feet.

Speaking of cable thickness, next section.

Thicker Cables Offer Less Electrical Resistance

The next factor is the thickness of the cable, or the cross-sectional area of the cable. The thicker the cable, the greater the amount of electrical current that it can conduct. This means that the thicker the cable, the lower the electrical resistance, and the lower the electrical resistance, the higher the sound quality.

The thickness of the cable is measured in gauge. The thicker a wire, the lower is its gauge. For example, a 12 gauge wire is thicker than a 14 gauge wire.

This means that once you have determined the ideal length of your cable, the next thing you can do to maximize sound quality is to choose one with the greatest thickness. This means choosing one with the lowest gauge value.

Suppose you have two choices of cables, 14 gauge and 10-foot long, and 12 gauge and 10-foot long, which one do you think would result in higher sound quality? The answer is the 12 gauge. Its lower value means that it is thicker and can offer less electrical resistance in the cable.

Wire Material

Aside from the length and the thickness of the cables, what else can affect sound quality? Different wire materials can also affect the electrical resistance and hence affect how well the cable can transmit electrical current. This means that the wire material is also something that you need to consider when thinking about sound quality.

Copper is the most common type of wire material. That's because it conducts electrical current pretty well, and is fairly cheap. It offers relatively low electrical resistance.

However, there is one caveat to copper. It does oxidize easily. Oxidation is a process in which metals interact with oxygen and change to become a different substance. Another word for oxidation is rust.

Oxidation occurs naturally over time when metals are left exposed to air. When copper becomes oxidized, it becomes copper oxide. This substance lowers the cable's effectiveness in conducting electrical current.

This means that when it comes to cable wires, oxidation is a process that we would want to try to avoid. We want the metal wires to be as well-insulated as possible. This means that a good cable would cover the metal wires completely so that no part of the wires are exposed.

Compared to copper, silver offers even lower resistance to electrical current transmission, meaning that it is an even better wire material than copper.

Why is it that copper is still the most commonly used material in cable wiring?

The answer is the price. As you can imagine, silver cable wires would cost considerably more than copper ones.

Gold is the most non-reactive metal, and it does not oxidize at all, meaning that it never rusts. This is a desirable quality for a cable wire to have. However, gold isn’t great in the electrical resistance department, as it offers greater electrical resistance than copper or silver.

Gold's higher electrical resistance makes it a less desirable cable material. It also loses out in terms of its price, since gold is the most expensive material out of the three.

The takeaway about cable wire materials is that different materials offer different amounts of electrical resistance, meaning that the material your wire is made out of will affect sound quality.

Note: Wire materials such as copper rust easily, so it should always be wrapped and insulated well. It also makes it safer to use.

Speaker Terminations

When you want to plug your cable into the source device or the speakers, it would be useful to have convenient speaker terminations designed to be connected securely and quickly.

There are two common speaker terminations: banana plugs and spade plugs.

Banana Plugs

Banana plugs are plugs inserted into your speakers' audio jacks or source device. They're called banana plugs because they look like unpeeled bananas. Once inserted into the audio jacks, they tend to stay securely fastened.

Space Plugs

Spade plugs are plugs that resemble crab claws. To plug them into your speakers or an electronic device, simply fasten them onto the binding posts on those devices. When fastened properly, they should provide a secure connection.

Choosing the cables with the right speaker terminations is not so much about sound quality as it is about convenience and the security of your connections. You wouldn't want to have poor, ill-fitting speaker terminations that fall off easily because that would interfere with the connection.

Speaker Cable Recommendation: GLS Audio 3 Feet Speaker Cable

This is an example of a speaker cable available on Amazon that has received good customer reviews. This product from GLS Audio has an average customer rating of 5 stars, making it one of the best-reviewed speaker cables on the platform.

At only 3 feet (91.4cm) long, it is a relatively short speaker cable. But as we have seen in this article, a shorter speaker cable would generally provide for better sound quality. Its wire is made out of copper. The copper is rated in American Wire Gauge (AWG) specification, which is of a higher specification than the more common Gauge (G) specification.

The cable wires are wrapped in a thick rubber covering. The rubber covering is 10.5mm (0.4 inches) thick, meaning that it is more than enough to protect the cable wires from external damage. The thick rubber casing also makes it flexible and durable. It also comes with a velcro strap that allows you to coil the cable for transport.

This wire is 12 gauge, making it a relatively thick cable. Its short length and comparative thickness mean that the electrical resistance is lower compared to many other cables on the market, and is the reason why customers are satisfied with its sound quality.

The only downside to this product is that some people find the cable length of 3 feet (91cm) too short. Some people's speakers are situated too far apart for this cable to be practical.

Some customers also complain about the bulk of the product, with the rubber covering being 10.5mm or 0.4 inches in diameter. However, the added bulkiness does protect the internal wires better as well. It weighs 5.6 ounces (159g) and has dimensions of 8.1 x 7 x 7 inches (20.5 x 17.8 x 17.8 cm).

Conclusion

Cable length does indeed affect sound quality – the shorter the cable, the better the sound quality. Sound quality is also affected by cable thickness – the thicker the cable, the better the sound quality. The reason for both of these is the law of physics pertains to electrical current and electrical resistance.

Sound quality is also affected by the wire material. The most common of which is copper. It is also worth choosing a speaker cable with convenient and securely designed termination plugs that can connect easily to any electronic device.

Here’s a breakdown of the post:

  • Cable length and thickness have a direct impact on the audio performance.
  • The material of the cable also affects the sound.
  • Short cables transmit better audio signals, as well as wide cables.