CAT 5 speaker cables have long been regarded as one of the best value for money DIY projects.  There are plenty of CAT 5 projects on the web, and in our opinion, the best one by far is “Triple Twist” from TNT Audio.  This article looks into the physical properties of these gutsy CAT cables.

The construction of these cables is four pairs (Blue, Orange, Green, Brown). Each pair consists of a colour and its mate.  The colour is the most dominate on a pair, with the mate mainly being white with a splash (or band) of the same colour.  In all cases the pairs should remain together, as a pair, as they optimise the balance and performance of the pair in relation to itself, and the other pairs.
The normal cable, purchased in the stores, is a solid core cable used for cable runs I a building how ever, the cable that is used for patch-chords in computer networks is multi stranded.  The attenuation characteristics of the multi strand cable are worse than the solid core cable.
Above is a diagrammatic representation of the cross section appearance of the three types of cable on the market.
All of these cables are designed to provide a positive ACR (Attenuation to Crosstalk Ratio) at a given frequency.  To have a positive ACR means that a signal can be defined from background noise.  Attenuation is a function of distance and frequency.  Hence increased distance and frequency leads to increased Attenuation.  Crosstalk refers to the amount of noise or interference introduced into a system.  It can come from internal or external (power hum) sources.  Cat 5can have a positive aCR at 100MHz, where CAT 6 has a positive ACR at 200MHz.  Cat 7 has a positive ACR at 600MHz.
While the performance parameters set for data cabling systems are way above the frequencies utilised in a Hi Fi system, minimising the reduction of noise in a system is the main function of these cabling systems.

This cable is designed to reduce noise in systems such that they can operate up 100MHz.  Cat 5 is readily available from almost any electrical hardware store.
This cables designed basically for the future market with an eye to reducing costs on the electronics associated with computer networks.  The system is designed to reduce noise to such an extent that a signal can still be deciphered at 200MHz.  Cat 6 may be slightly more difficult to find in the stores.  You could possibly expect to pay 50% or more for this type of cable above CAT5.
An interesting cable in so much as it is supposedly reaching the performance limits of copper cable in computer networks.  Its noise reduction properties will be second only to optic fiber (which picks up no electrical noise) The biggest problem associated with CAT 7 is the fact that it is a shielded system, and as such earthling of the shield is of vital importance.
Ref. MAC, MW 2001