Audio Cables

The most used audio cables are generally the high end coaxial audio cable. High end audio cables are claimed to improve the sound quality of high-fidelity audio systems but whether they actually do is hotly disputed. Since the audio signal passes through cables on its way from the source to the amplifier, or from the amplifier to the speakers, the cables will affect that signal. Basic system frequency response can be calculated from the electrical properties of the cables, and components on either side of the cables. These electrical properties include resistance, capacitance, and inductance. For small-signal applications the degree of shielding are also important. High-end cables for the audiophile market often involve intricate construction geometries and exotic materials such as silver and oxygen-free, long-crystal, high-purity copper.

There is controversy among audiophiles surrounding the impact that high-end cables have on audio systems. There are claims that, even among audiophiles, in a double-blind test it is difficult or impossible to distinguish extremely expensive, exotic speaker cables from ordinary lamp cords or budget 12AWG copper speaker wire. James Randi, a stage magician and scientific skeptic best known as a challenger of paranormal claims and pseudoscience, offered a prize of one million dollars to anyone who could prove his or her ability to distinguish an expensive high-end audio cable from an ordinary audio cable by means of a controlled listening test. Michael Fremer of the Stereophile magazine took the challenge, but satisfactory testing conditions could not be agreed upon, and the test did not take place. Anecdotal testing can lead to believe that audiophiles can tell high end from low end cables, but serious and controlled testing hasn't shown such thing so far, unless some of the cables at test are broken. One of the more contentious areas is in digital cable design, with high end cables being sold with claims of "distortion-free signal transfer." Some have argued that since the bit rates, i.e. approximately 1 Mbit per second and distance traveled are considerably lower than for other data transfer technologies such as gigabit Ethernet, any cable appropriately matched to the correct impedance requirement is sufficient. Others claim that jitter caused by imperfect impedance matching is very detrimental to the audio signal and the most substantial shortcoming of digital audio. This has led equipment manufacturers to design new standards such as I²S which separates clock and data signals or implement buffering and re-clocking, although such standards are typically aimed at synchronising multiple signals to a single clock rather than attempting to correct inaudible errors due to jitter. It is also worth noting that in independent testing, digital audio, at least of the S/PDIF sound format has been shown to be carried perfectly well over any length of wire of nearly any quality, including wire as simple as a coat hanger. Skeptics say that a few meters of cable from the power amplifier to the binding posts of the loudspeakers cannot possibly have much influence because of the complex crossover circuits found in most speakers and particularly speaker driver voice coils with several meters of wire. A global concern with speaker cables is their inherent impedance relative to the impedance of the loudspeaker. Low impedance speakers are claimed to benefit most from low impedance cabling; this means thicker and/or shorter wires. It is claimed that longer cable runs need to be even thicker to minimize signals.