Did you know that some audio cables are good in the bass but may sound bright or harsh at higher frequencies?

Audio cables have always been, and will continue to be, a contentious issue.

Many technocrats refuse to believe that cables can make an audible difference to a music system, claiming that a piece of wire is just a piece of wire.

But try telling your electrician you want to install heavy solid-core mains wiring in your audio system and see what sort of reaction you get.

Several different cables are used in today’s audio systems.

Power cables connect system components to the mains. Some aftermarket versions are noticeably better than others, but in terms of sound quality they are probably the least significant cables in the system.

Digital cables are most commonly used for linking a DVD player and an AV receiver. These are becoming obsolete now that HDMI cables can transfer audio and video information digitally from the source to the amplifier, and from the amplifier to the video device.

The most significant cables in an AV system, from a sound perspective, are speaker cables and interconnects.

Speaker cables connect the amplifier to the speakers, and interconnects are used for connecting electronic components within your audio system, such as a CD player to an amplifier.

The cost of these cables can vary from nothing – a cable that comes with a CD or DVD player – to many thousands of dollars.

Beware of cheap or ‘free’ interconnect cables, as they can sound particularly nasty. They are typically thin, bright and brash. On many occasions I have dramatically improved the sound of a modest system by changing the interconnect cables between CD player and amplifier.

By replacing the interconnect cables that came with the system with a pair selling for as little as $40 the resulting sound can be much smoother, richer and more involving.

The best way to assess cables is to listen to them, preferably on a system similar to yours. Alternatively, the better audio dealers can usually advise on the most suitable cables for your system.

Looking at specifications or the cable configuration gives little indication of their sonic quality.

All else being equal, a cable made from high-purity copper will sound better than one made from a lower grade. High-purity silver may sound better again, particularly in the treble, though at a much higher price.

It is usually preferable to use high-quality copper cables than similarly priced, and therefore lower quality, silver cables.

In my experience, all the top-quality silver cables carry top-shelf prices.

In a system containing a CD player, a pre-amp and a power amp, the CD player to pre-amp is the most critical position.

When using two different types of interconnect, use the better ones between the CD player and pre-amp rather than between the pre-amp and power amp.

This is because the signal from the CD player has one more stage of amplification to go through (the pre-amp), thereby magnifying any signal quality deviation caused by the interconnect cable.

Speaker cables can also make a big difference to system sound quality and are as much a ‘black art’ as are interconnect cables.

There are many different configurations on the market; some simple configurations can sound excellent and others can sound poor.

The same can be said for complex configurations. The one consistent factor affecting the sound quality of audio cables is the purity of the copper or silver being used.

Most of the very thick speaker cables made for car audio that I have heard sound quite bad. I suspect that the copper purity is not particularly high. Impressive appearance is probably a higher priority than impressive sound for these.

Some speakers are bi or tri-wireable, having two or three sets of terminals. If you use bi-wireable speakers you should take advantage of this feature by using two sets of speaker cables or a bi-wired cable, which contains four conductors.

The two sets of cables are joined at the amplifier but are separate from then on.

When bi-wired, speakers generally sound more open and more transparent.

The main benefit of bi or tri-wiring speakers is that you can choose cables that are optimised for the appropriate frequency range.

For example, some cables are particularly good in the bass but may sound bright or harsh at higher frequencies.

Other cables may sound smooth and detailed at high frequencies, but thin in the bass.

Others again may sound delightful in the mid-range but not so good in the bass and treble.

Choosing cables that are optimised for their particular frequency range can bring about considerable audible improvements.

Although bi and tri-wired speaker cables are connected at the amplifier, the crossover network built into the speakers ensures that bass travels along the bass cable, mid-range along the mid-range cable and treble along the high frequency cable.

With a well-designed crossover network, the bass section has lowest impedance at bass frequencies, the mid-range section at midrange frequencies and the treble section at high frequencies.

Since electricity always follows the path of least resistance, bass frequencies will travel along the bass cable, mid-range along the mid-range cable and treble along the high frequency cable.

I consider cables to be yet another component in any audio or AV system. Improving the quality of cables can often be as important as upgrading the amplifier, yet it is so easy to overlook them and compromise your system.

The burning question is how much one should spend on cables.

This will depend on the value and quality of the system they are going into. It is pointless adding exotic expensive cables to a modest system. Although they will probably improve the sound, the low quality of the system will minimise the benefits.

On the other hand, it would be silly to compromise the sound of a high-end system by using anything but high-end cables.

There is no hard and fast rule, but you should budget for 10-20 % of the system value to be spent on cables.