There’s a saying in the professional audio world that a sound system is “only as good as its weakest link.” This refers particularly to low-quality audio cables. In order to get the most out of a pair of high-quality speakers and/or stereo receiver, audio cables of similar quality should be part of the chain.
What makes a good audio cable? There are several factors. Aside from the fact that, like most products, better cables are ones that are designed to last longer, the high-quality kind are also built to provide the cleanest signal possible.
For instance, cables that are made with copper and/or gold tipped input jacks are better suited to conduct electricity and are less likely to corrode, which can degrade the sound. Another example is how the wiring inside a cable is protected. High-quality cables are built with a braided plastic twine between the rubber exterior and the wiring carrying the signal. The reason for this is that the wiring within a cable is susceptible to pick up a buzzing sound, known as 60-cycle hum, from other electronic devices or from the electric currents within the wall of a house. A tight and sturdy braid acts as a shield to this noise.
Because of these factors, the difference in the price of audio cables can vary extremely. The first determining factor is, of course, the length of the cable, but the rest are based on the quality of materials (gold, cooper, etc.) and the craftsmanship with which the cable is constructed. Aesthetics can also be a factor in price, but this should not affect the sound of the cable.
Whether or not top-of-the-line audio cables are worth the extra cost is debatable. The only way to really grasp the difference is to try an A/B comparison in person. One thing is for sure: those who grow accustomed to the long-lasting, noise-free cables may find it hard to go back.