Interconnect and speaker cable (referred as cable) is important components in the hi-fi or home theater system. Selecting the appropriate type of cable will help sound be better and help you exploit all capacities of the system.

The concept of cable in the hi-fi system that we are talking in the limit of kinds of interconnects at low-level and high-level among devices in the system. In fact, we may be classified as follows:
 


Interconnect: is responsible for transfer of low-level signals ( from a few milivolt to several volt) between source devices (disk, CD player, tuner, Video player) with DAC, preampli and between preampli to the ampli capacity. 
Interconnect has also some kinds such as:

- Unbalanced Interconnect: usually has two cores and the plug as RCA type (lotus). It is also known as single-end.
- Balanced Interconnect: has three cores and use conductor as XLR type. It is often used for the devices with balance input and output.
- Digital Interconnect: is a single interconnect to transfer digital signal, usually from CD transport or other digital sources to digital processors. Digital has a type of metal (coaxial) and type of plastic or glass organic (optical).

 
Speaker Cable: is responsible for transfer of high-level signals (from a few to several hundred volts) from ampli to the speaker system.
Speaker Cable has also some kinds such as:

- Single-end: each has only two link points. This is the most popular style now.
- Bi-wire, Tri-wire: each have 2 or 3 link points for the speaker may connect with 2 or 3 independent sound link.
- Speaker Cable with many types of plug such as: straight metal, curve metal, banana, crabs... in which the top of banana and crab are the most common in high-level speaker cable. If there is no requirement to remove so much, you can put directly a ceiling speaker cable to ampli and speaker picket is also very good.

Structure of cable and signal cable
Speaker cable and signal cable usually consists of three components: fiber, the electricity (insulation), and plug. Fiber is for signal transmission, electricity is insulation covering the fibers and outside; and plug is the connector between the cable and audio equipment. These elements are gathered into physical structure, called the configuration of cable. Each component also affects on the sound characteristic of cable.

 


Fibers are usually made from copper or silver. In high-class cables, the purity of copper is very important. A copper alloy contains a pure copper quantity and a partly of extraneous matter. For example, a fiber with 99,997% pure copper, that is, it contains 0.03% of the other ingredients (may be iron, sulfuric, aluminum ...). Many people believe that more pure the copper is, more excellent the sound is. Many copper alloys have been called OFC (copper is not soaked by oxygen). When manufacturing OFC copper wire, it had been eliminated most oxygen component, or saying exactly that it had been withdrawn from copper alloy because actually, it can not be eliminated completely out of oxygen. Thus, copper will be a little oxygen, make sure to keep the core wire is capable of transmission stability.

A material commonly used for manufacturing the core wire is silver. Wire is usually made from silver is more expensive than copper, but also has its advantages. Although the electricity capacity of silver is only slightly higher than copper, but silver is oxygen less than copper. Electrical solvent is an insulator surrounded around the fiber. This solvent absorbs energy is called the phenomenon of absorb the energy of electrical solvent.

In cables, this phenomenon can affect on the signal. Therefore, an electrical solvent have a big impact to the sound of cable and each of electrical solvent also has different influences. Common cable type is used cheap plastic as substance, and better one is usually used polyethylene. It is best to use polypropylene or even Teflon. Some companies manufactured a material as almost air to be insulator (of course the best insulator is a vacuum). There are other companies pumping the air to substance so that create an alloy containing much air.



A plug is part of the cable. Good plugs will make sound more better. Users always want the plug of wire contact widely and tightly with the socket of equipment. Some kind of RCA plugs maybe has small gaps in the middle of socket base to enhance a contact with socket. Most of high-level RCA plug are usually made from normal copper with a bit of brass to increase the hard for material. This alloy is usually dipped in Nikkei, and then dipped in gold to avoid oxygen. In other plugs, gold is dipped directly onto the brass. Some materials are used for plug are gold and ro-di.
RCA and speaker’s plug is welded directly with the core.  Most manufacturers use the welding mixed a little silver. In the modern welding technique, it is not used welding substances but welding directly fiber with plug by using a big current to melt the contact point between fiber and plug, making them linked together and improving the ability to transmit signals of the cable.