[Home Theater Network HDAV.com.cn] The importance of wire to sound, I believe that audio equipment users will have a strong experience. To make a metaphor, the wire is like a road, the signal is a car, the road is in good condition, and the car goes smoothly. Therefore, the importance of wire is self-evident. HI-FI and cinema HI-FI have the highest requirements for wire and the most obvious and outstanding impact. Since the meaning of HI-FI itself refers to high-quality, high-grade equipment, it is difficult to define the investment proportion and brand of the wire for a set of "fever" sounds, as long as the sound effects of the audio equipment can be exerted. No matter which brand you use, the wire must always follow one principle: try to make the equipment achieve a true balance and the best natural sound. This requires long-term practice and rich audio knowledge and technology. In terms of cinema, the investment in wire rods should be high, and the investment ratio should not exceed 20% of the total audio equipment unless you have special effects. Cinema equipment should express the sense of envelopment, movement, positioning and speed of space, but in these performances, we must not forget that the image that affects our visual effects in the theater is the image, which makes us lower Requirements for changes in sound quality. 1. What effect does the wire have on the audio signal? The design purpose of the signal line or the speaker line is to make the music signal not change during the transmission process. However, in actual use, the general wire is like a filter, and they have resistance, capacitance, inductance, etc., which will be the signal of the pair. The effect is such that the signal is underdamped in transmission, losing music information and details. Due to the presence of capacitance and inductance, the transmission cable has its own special frequency characteristics, that is, different delays (also called different transmission rates) and different impedances for signals of different frequencies. Obviously, this will cause signal generation. Certain distortion The music signal is not only 50 or 60hz like electricity. It also contains various frequency components in the process of flowing, not only to withstand large energy, but also to transmit complex music signals without loss. 2. What kinds of signals are transmitted by wire? 1) The standard level signal line refers to the connection line between the sound source and the power amplifier. Its transmission level is about 1V, which is also a shield type transmission line. This type of wire is the most widely used in the audio industry. Interestingly, wires made of different insulating media and metal materials have a subtle effect on sound quality. For this reason, manufacturers have produced a variety of wire types to meet people's needs. Different levels of music appreciation requirements. The high-grade finished wire is made of nylon braided sleeve coated with anti-static layer, lined with metal shielding sleeve and then made of oxygen-free pure copper as core wire, and then with gold-plated plug to prevent the plug from contacting badly and generating noise. 2) The strong signal line refers to the connection line between the speaker and the power amplifier. Such a line often has no shielding layer. For this kind of wire, the key is to reduce its resistance because the output resistance of the modern power amplifier is very low, so the speaker line is The requirements are also increased, such as the choice of large cross-sectional area or stranded wire. The wire is from pure copper to silver wire. The speaker cable of the more expensive price is the special line of oxygen-free copper speaker. Its main feature is good electrical conductivity and low resistivity. It uses it to increase the sound when playing back the sound. less. 3) The weak signal line refers to the connection between the microphone to the preamplifier or between the digital source and the decoder, usually a shielded line. Digital lines are such weak signal lines. Due to the greater improvement in the fax degree and sensitivity of current audio equipment, the requirements for signal transmission are also getting higher and higher, but the signal line is used to transmit digital pulse signals or audio AC signals. Its transmission principle is more than normal. DC power transmission is much more complicated. In addition to the current flowing through the wire, it can be affected by the resistance of the wire and generate a magnetic field. There is also the effect of skin effect and phase distortion between high and low frequencies. The wire should transmit the full audio segment with balance and low distortion. (20Hz ~ 20kHz or wider) signal, then the design of the line must be very strict, only in this way can the signal be amplified by high-fidelity, the sound is restored by the speaker. 3. What is a good wire? 1) Good contact, good durability after multiple insertions and removals. Poor contact is prone to inferior or even disconnected sound or image signals, which is by no means acceptable to consumers. When we use various audio-visual equipment, we will inevitably remove and plug the wire several times for various reasons such as maintenance, changing the position and changing the machine. A high-quality wire must not be inserted and removed many times. After that, there is a phenomenon of poor contact. 2) Very low transmission loss and good shielding performance. The main purpose of the wire is to transmit the signal. The ultimate goal pursued is to transmit the signal in a true and complete manner without causing signal loss or distortion due to the material and structure of the wire itself. Therefore, the impedance and capacitive reactance of the good wire itself should be well matched with the equipment, so that the signal can be transmitted 100%. 4. How long is the wire suitable? 1) The length of the speaker cable should be 2m~2.5m, which is close to the practical length, and there is a certain room. If it exceeds 5m, the sound range will be narrowed, and the aftertaste and intensity of the music will decrease. Unnecessary waste. 2) When using a hard beam speaker cable, do not bend the wire too much. When using a multi-strand speaker cable, the wire diameter and the terminal contact surface should be large and firm. 3) It is better to choose the length of the signal line from 1m to 1.5m. Because most enthusiasts compare the audition, they think that the signal line is slightly longer, which is good for sound quality and easy to move and adjust. (Note: For digital wire, the foreign HEADFI website believes that the shorter the digital line, the better the effect) 4) When the self-made signal wire is used, the gold-plated yellow plug is solder-free. When the screw is used for fixing, the head resistance is generally 5~50mΩ. When the welding process is used, the interface resistance is below 3MΩ, so it is better to use soldering instead. 5, wire indicators According to different smelting processing methods, high-purity copper can be subdivided into OFC oxygen-free copper, LCOFC copper, PCOCC oxygen-free single crystal copper, Super PCOCC copper, etc.; according to its purity, there are 4N, 5N, 6N, 7N, 8N, etc., where N stands for 9 (Nine), 4N means that its purity is above 99.99% (ie, there are 4 9, called 4n), and so on. There are too many wires on the market that are known as 6n or even 8n. The most outrageous is the so-called 9n silver wire. A large scale copper smelter can produce 4n copper. Further chemical removal of oxygen and other trace metals can increase the purity, but the instrument does not necessarily measure it. For more fresh and fun home theater information, please pay attention to the home theater network: , the most influential home theater audio player interactive media website. Note: This article is transferred from love video IP 20 frequency inverter for three-phase asynchronous motors, specially designed for pump and fan applications in the following market segments: Water & Wastewater, Oil & Gas, building management and energy plant. Three Phases Inverter Elrctric,Period To Frequency Converter,Three Phases Frequency Converter,Wavelength To Frequency Inverter Wuxi Trenty Machinery & Equipment Co., Ltd. , https://www.elec-inverter.com
