Acoustic shielded cable: features and types

To achieve high-quality sound when installing an audio system, you need to pay attention to all components - speakers, amplifiers and, of course, an acoustic cable. Get a sound of high quality even from an expensive system will not work if you use a conventional wire. A shielded cable is what you need to connect the signal source to the playback devices. Otherwise, you will have to listen to the interruptions between the tracks.

Acoustic cable

A modern acoustic cable is two or more conductors of electric current placed in insulation made of polyvinyl chloride, Teflon, polyurethane and other polymer materials. The wires are electrically identical, but are marked in different colors so that the user does not mix up the polarity during the connection, uniting the devices. The main material is copper. It has the lowest electrical resistance, which makes it possible to achieve high sound quality. However, during laying, the cable can pass near the power lines. Because of this, there will inevitably be magnetic fields, eddy currents, which will significantly reduce the sound quality.

To avoid such a problem, use a special wire - shielded. This cable has a special protection from metal or plastic, which is a kind of "screen" from electromagnetic interference.

Types of acoustic cables

In order for a normal shielded wire to cope with interference protection, it must be connected to earth, that is, grounded. In some cases, this action is simply impossible. That's why the balanced cable was invented. If there is only one central "core" in the usual conductor, which carries the main signal, then in the balanced cable there are two of them - hot and cold. They both carry the same information, but with different "similarities." The effectiveness of such a line depends on the balance of such rods.

The Star Quad cables are a good protection, in which two pairs of "rods" are isolated and in parallel connected to each other, which provides a high level of protection. Specialists distinguish the so-called conductive wire, screened with plastic. This type of cable is effective at short distances, for example, when installing an audio system in a car.

A separate group can be distinguished microphone cables, in which the protection is made of woven material. But the most universal and providing the best protection are wires with a foil shield.

Wires with foil protection

Cables with foil protection between themselves differ in the material from which the screen is made, as well as the type of braid. There are four types of electromagnetic protection:

• Foil copper or aluminum screen - provides good protection of conductors from EM interference, but is susceptible to bends, turns (protection bursts and cracked);
• Copper wire mesh braid - wire shielded in this way, creates the best protection against interference, but has a very high price (used in professional equipment);
• Spiral braid made of copper or other non-ferrous metals - such a cable is almost not susceptible to mechanical impact and protects well from interference.

The fourth type is a cable with a combined screen, which combines the useful properties of solid foil and various types of braids. They are distinguished by the average price, large assortment and high protection rates.

Conductor resistance and sound quality

The specific electrical resistance of the conductor has a decisive influence on the sound quality. The resistance of an acoustic line depends on several factors - material, cross-sectional area and cable length. The best sound quality can only provide copper wire shielded with foil. At the same time under the insulation layer there must be at least 20 cores. If, on the other hand, the cross-sectional area does not exceed 2.5 mm ² , and the cable length is within 3 meters, the resistance will be zero. Accordingly, the sound quality with such a wire will be the best.

The parameters of the conductor affect the equipment. Thus, long wires have a large capacitance and inductance, which creates an additional load on the amplifier.

Interconnector Cables

The inter-unit cable is a conventional conductor, at the ends of which there are special plugs for connection to the equipment, or to the blocks. Interconnected shielded cables, wires have some difference from conventional acoustic lines. In particular, the sound quality here does not depend on the type of protection, but on the material of manufacture. Identify the material by marking:

• SSs HI END SP - this is how acoustic lines made of copper with a silver coating are indicated, able to create the best sound quality.
• EMT OFC sc - the abbreviation used to refer to wires made of oxygen-free copper, the quality of the transmitted signal is second only to the previous representative.
• AHpsc 16 GA is simply high-quality conductors.

If you are looking for cables that can transmit a signal without any distortion, then you should pay attention to the copies made entirely of silver. Such products cost hundreds of dollars for 1 meter, but the quality of the signal transmitted by them is not comparable.

Stranded cables

A special place in the market of acoustic equipment is a shielded multi-core wire. In such a conductor under the layer of insulation there are several interwoven veins. They have a number of advantages over single-core cables:

1. High elasticity - wires are not afraid of kinks, turns and other mechanical effects.
2. Low current losses - which is due to the transmission of the signal at once by several "rods".
3. High-quality switching - the processes occurring in the first seconds after a short circuit (when switching the toggle switch, for example), have no effect.
4. High reliability and durability - the service life of such products is an order of magnitude higher than that of single-core ones.

This type of cable has some drawbacks. The main one is high cost. So, the price for wire shielded double-core can reach 1500 rudders. In addition, such conductors are not intended for operation in high-frequency networks.