Guide to Home Theater Cables
Cable Quality, Cable Length, and Performance Implications

Why?

Poor quality cables and inappropriate home theater wiring installations can allow noise and interference to compromise the signals from your system components, resulting in an unpleasant home theater experience.

Furthermore, insufficient cable bandwidth response and inappropriate conductor thickness may impair the transmission of the full signal information between system components, leading to loss in picture detail and sound clarity.

Unfortunately, the vast selection of available options on the market for audio video cables and speaker wire, as well as the different quality levels to choose from can at times be confusing. 

Cables Runs and Performance Implications

It is very important to fully understand how the issue of cable quality fits into the overall performance equation.

The truth is that if you want to get the best results, you wouldn't fit low-end tires on an expensive sports car. In a similar manner, do not expect to enjoy the best performance from your expensive system components with cheap home theater cables and interconnects.

BUT Wait! 

Don't just throw away those 'free' AV cables that came with your gear. If you have very short cable runs, most probably, there will hardly be any perceptible difference in system performance if the connectors on your cables provide a good enough fit.

What constitute a very short cable run depends on the application (i.e. video or audio), the respective system components, and the signal levels involved. For example, in the case of speakers, cable runs of less than 20 feet (approx. 6m) make less of a difference.

On the other hand, the use of larger speaker wire in the case of either relatively long runs (over 30 feet) or very low impedance speakers (less than 4 ohms), will help deliver more of the amplified signal to the speakers.

The same holds true for video cables. Low-resolution signals, like NTSC or PAL, don't require thick wires. A decent-quality S-video interconnect can run up to a hundred feet; poor-quality video cables wouldn't.

Cable Length and Connector Quality - Practical Considerations

Up-converted and high-definition signals should ideally run over short lengths using regular size cables; use of mini-type cables may adversely affect signal quality especially as cable length increases.

However, we have just stated that what constitute a 'short' or 'long' cable run depends mainly on the type of AV interconnect itself. Below, we list the typical maximum cable runs you may expect for the most common AV cable types.

• For composite and s-Video, standard, inexpensive video cables should allow runs of up to 15 feet with no apparent deterioration in picture quality. At 15-feet, cheap s-Video cables may lack slightly in picture clarity especially when displaying fine color detail. However, at these shorter lengths, the quality of the connectors used on these cables will have more impact on the resultant picture quality than the quality of the cable itself. In order words, do not overlook the quality of the connectors used on your AV cables.

For longer distances, an RG-59 cable can be used for runs of up to 60 feet with no perceived deterioration in signal quality. Use of the thicker RG-11 cable should enable distances of up to 100-feet with no problems.

• Component Video is more demanding; use of RG-59 cables can support up to around 33-feet while RG-11 cables support up to 80-feet without any loss in perceived picture quality.

• High resolution (VGA, SVGA and XGA) computer signals require the use of appropriate VGA cables. Good quality VGA/XGA cables can run up to a maximum of 30 to 35feet though some picture quality may be apparent at the longer length. Cheap VGA cable would not handle XGA resolutions beyond 4-feet runs.

• DVI is limited to a maximum of 15 feet. HDMI is designed to perform better over longer lengths, supporting up to about 50 feet.

Longer cable runs are possible for each of these AV interconnects but use of expensive high quality cables and high-grade connectors is essential. In addition, longer lengths would often call for specialized technology using inline amplifiers, twisted pair, fiber-optic and RF solutions to solve issues like signal attenuation, instability and noise, arising out of the use of long cable runs.

Handling of audio signals over long cable runs is less demanding but these can still create various problems especially when dealing with low line-level power signals where noise pick-up and high cable impedance can lead to signal deterioration. Aim to keep line-level audio cables as short as possible unless you are using balanced cables; the latter support longer cable runs.

Driving of high power loudspeaker signals is again dependent on the appropriate speaker wire thickness; for the recommended speaker wire gauge with wire length, please refer to our speaker wires guide.

In the case of digital audio, these can run over longer lengths than their analog counterparts using either relatively inexpensive fiber-optic cables, or RG-59/RG-11 coax cables as used in the handling of composite video signals.

A few DON'Ts worth taking note of:

Always opt for the best possible home theater cables you can afford should you decide to upgrade the 'free' AV cables that come with your gear but don't just equate quality with a higher price.

On the other hand, don't just upgrade for the sake of it; if the AV cables delivered with your gear are of decent quality, and you only have very short cable runs, use of a more expensive cable would probably make not much of a difference in system performance.

Don't opt for superior quality if decent quality home theater cables suffice for your needs. There are plenty of affordable, decent-quality home theater cables that will still allow you to enjoy better sound and clearer picture should there arise the need to replace your 'free' interconnects.