The age old argument of cable quality has raged between audiophiles since the dawn of time (well not really, but certainly for quite a while). Some argue the quality of speaker cables is just as important as the quality of the Hi-Fi components they’re connecting. Other enthusiasts save their cash buying budget cables and claim that they make no difference to the sound quality whatsoever. The following article is based on one written by our colleagues at Cambridge Audio in England, although we have expanded some parts to add further clarification. The goal here is not to poke our nose between these two opposing camps and risk getting dragged into the ongoing battle and instead offer up an overview of speaker cable jargon and give you some useful tips on how to buy your own.
What Is Speaker Cable?
Speaker cable is the wire used for the electrical connections between speakers and amplifier sources. It has three key electrical properties: resistance, capacitance and inductance. Resistance is by far the most important property to look at. Low-resistance wire allows more of the source’s power through to the speaker coil, meaning more power and more sound. Simple enough.
How Does Resistance Affect Performance?
Generally speaking, resistance starts to have an effect on the performance of a speaker when resistance is greater than 5% of the speaker’s impedance. Resistance is affected by two key aspects: wire length and the cross sectional area of the wire. The shorter the wire is, the less resistance it will have. The trick here is to minimise wire lengths where possible but still ensure your speakers are positioned apart. It’s also important that the wire lengths to both speakers are similar in length to ensure they both have equal impedance values.
The cross sectional area of the wire is referring to the thickness, or gauge, of the wire. The guide is the American Wire Gauge (AWG) chart which although an imperial measurement is basically the world standard the audio industry uses. Anyway, the lower the gauge number means thicker cable and less resistance and the higher the number the thinner the cable and, the higher the resistance. It is therefore a combination between speaker impedance, length and gauge that affects the resistance. The below table illustrates suggested cable lengths that will ensure your cable has a resistance less than 5% of your speaker’s nominal impedance given differing gauge measurements.
Copper is the most widely used material for speaker cable due to its low cost and low resistance. However, copper does oxidise so it needs to be well covered and insulated. When exposed to air, pure copper reacts to creating copper oxide which covers the exposed surface; this creates a barrier between the cable and the speaker/ amplifier therefore can weaken connections. Silver is slightly less resistive than copper meaning a thinner gauge will still offer a lower resistance, however as you might have guessed silver is expensive so a thicker copper wire will actually still be cheaper to buy. Gold however does not oxidise so it can be used for open terminations but as it has a higher resistivity to copper or silver it is rarely used as speaker cable. As with all metals, the purer the wire used, the higher the cost (per metre). Many different levels of purity are available for cables, and whether or not this brings a significant benefit to the audio is down to personal preference and for you to decide for yourself.
Specific terminations are available to use at the ends of your speaker wires to aid the connections to sources and speakers. The most popular options are oddly and hilariously named banana plugs and spade plugs. Their main benefits are that quicker and easier connections can be made as they simply plug into the speakers terminals, additionally, when fitted properly they ensure a solid and reliable electrical connection whilst minimising risk of shorting due to stray filaments of wire touching adjacent binding posts. If you’re going to change/modify/move parts of your system regularly then it may be a good idea to use terminations purely for ease of use. If you’re just going to plug your speakers in once and listen for years then you’re probably fine to just use normal wire binding.
Bi-Wire Or Single Wire?
The final option with speaker wire is whether to bi-wire or not. If your speakers only have single wire connections then of course it makes this decision simple –single connections it is! But if your speakers have two sets of speaker connections then they can be bi-wired. A perceived benefits of bi-wiring is that it can create a more open sound stage and increase levels of detail, but it’s argued that single wiring in fact offers a more musically coherent sound. Again this is one for the die-hards to continue arguing with, but bear in mind that equivalent quality bi-wiring is almost always more expensive than single wire configurations.
In addition to these key features there are many electrical properties claimed by cable manufacturers such as additional insulation and better purification of oxidising materials to improve sound quality. However, the difference that these features have on the end result is rather undecided; the most important consideration is that your wire gauge is suitable for the impedance of your speakers and the length of your wire. Anything beyond this it is a matter of subjectivity. There are different sound preferences for different listeners, and different cables can sound different with different equipment so talk to us about your choices. Also please be reminded that price is not everything. Some conclude that you spend about 10% - 15% of your total amplifier/receiver/speakers budget on speaker cables and that is still a good guide. There are several good cable brands that offer quality product at quite modest prices as well as esoteric products for those who simply need to know they have the best.
It is our belief to sell products that we have used over many years and that offer a high level of both integrity and performance no matter what the price point.