Is high-end cabling an effective way to enhance your media experience - or a cynical rip-off? Darien Graham-Smith examines the technology
Although more and more technologies are becoming wireless, cable-free audio and video systems are still the exception rather than the rule. Until they become ubiquitous, you can bet electronics retailers will be urging you to buy expensive "premium" cables for your home entertainment devices, rather than relying on the cheap and cheerful interconnects you can buy for a few quid - or which may even be included in the box.
There are good reasons to avoid cheap cables. If you regularly move your equipment around, tension and twisting can cause a poorly made cable to break or develop an annoying intermittent fault. A wobbly plug can cause problems, too. Expensive cables are more likely to fit securely into their sockets, and to survive being repeatedly plugged and unplugged, trodden on in the night and chewed by household pets.
This is only part of the equation, however. Manufacturers and retailers of premium audio-visual cables don't only claim their offerings are sturdier, they also promise better overall picture and sound quality - justifying prices that can be five or ten times as high as bog-standard cables. Indeed, the argument goes,it's a false economy to use a cheaper cable, as you'll be missing out on the full capabilities of your hardware. Is there any truth to such claims?
Resistance and interference
It's a fact that cables don't all perform identically. Whenever an electrical signal travels down a wire, it loses intensity - a phenomenon called attenuation. This is mainly due to electrical resistance, which is proportional to the length of the cable and inversely proportional to its thickness. In other words, if you connect your loudspeakers to your hi-fi using a long, thin cable, the signal will degrade significantly, possibly to an extent that's audible as distortion. Using a thick cable that's no longer than it needs to be minimises this effect. Gold-plated connectors can also help to a small extent; ordinary copper connectors corrode over time, increasing overall resistance.
A second consideration is shielding. Domestic audio and video cables often end up running alongside power cables, which can cause interference. This may manifest as unwanted noise in the audio stream, or a speckled or unstable video image. High-quality cables may incorporate better shielding than cheap ones, meaning you can run them wherever you like without interference becoming a problem.
Logically, you'd expect a high-end audio cable with low attenuation and good shielding to produce a better sound than a cheap one. Indeed, hi-fi enthusiasts often praise expensive connectors for maintaining the tonal balance and expressiveness of music, while criticising the "thin" sound of cheaper cables.
There's no doubt that very cheap cables can be so poorly made as to conspicuously degrade the sound quality. But it's fair to say that not everyone hears a difference between regular cables and premium ones - leading sceptics to suspect that in reality there's no audible difference, and that audiophiles who claim to hear one are deluding themselves.
Testing the benefits
Over the years, researchers and reviewers have carried out numerous experiments to test whether listeners really do consistently perceive some audio cables as better than others. Some results have suggested that cables can indeed improve sound quality: earlier this year, the Audio Society of Minnesotaconducted a series of blind tests with more than 50 participants, and found a slight overall preference for the sound from more expensive hi-fi cables. Another interesting test was carried out by AVReview in 2008: here, most participants couldn't hear a difference between an £8 cable and a £500 one, but one panel member did consistently get it right.