To achieve contact transmission, communication, etc., between equipment and equipment in the sound system, they must rely on their connecting tools, which is the wire and connector. It occupies a very important role in the whole sound system, and now there are more types of cables and connectors used in professional sound systems. The following Shenzhen Yihe Audio Company makes a brief introduction to the common types of cables and connectors:
Various commonly used professional audio cable categories:
1, professional audio cable
Now common professional audio lines have two cores, three cores, four cores, five cores, etc., this line can be used to transmit high-quality audio signals due to good shielding effect; Now more professional microphones generally use more than three core wire, this wire anti-interference ability is strong, can do long-distance transmission. Of course, this wire can also transmit other signals, such as DMX512 control signals that transmit computer lights.
2, coaxial cable
This coaxial cable is generally used in video, there are also some as audio lines, because this wire anti-interference ability is poor, coupled with the design is not mainly used to transmit audio signals, so it is not suitable for long-distance audio signal transmission.
3, centralized cable
That is, multiple signal lines are wrapped in the same protective tube, which is generally used inside the connected system to reduce the number of independent wires. It is now also used for such special purposes as television broadcasting vehicles, underground burials and other special purposes. This kind of line is generally processed by professional manufacturers, and the quality is more guaranteed.
4. Optical Fiber
A transmission cable commonly used on many CD, MD and other recording and playback equipment, which transmits digital signals. With the popularization of digitalization, optical fiber will be used more and more in sound systems in the future.
5. MIDI line
Usually a five-core wire that transmits information about MIDI, this type of wire is now mostly used in keyboards, effects and other devices. It is usually possible to purchase a variety of commonly used MIDI wire connected finished wire; And the transmission quality is also good; So I won't go into detail here.
6. Other types
There are also some special wires, such as the multi-core network cable originally used to connect the network in the computer song on-demand system can now also be used to transmit audio and video, to achieve automatic on-demand computer function.
Various commonly used professional audio connectors Category:
1、xlr
Commonly known as Cannon joint (Cannon), this joint is composed of three contacts, respectively 1- Ground ground; 2-- hot end (level); 3- cold end (- level), of course, some equipment stipulates that 3 is the hot end (level); 2 is the cold end (- level), which should be clearly read the instructions of the equipment. Cannon connector is the most widely used type of connector in professional audio system, which can be used to transmit all kinds of audio signals in the audio system. The general balanced input and output terminals are connected by Cannon connector. In a sense, the use of cannon connectors is also one of the characteristics of professional audio systems different from civilian audio, and its benefits are:
a, the use of balanced transmission mode, strong resistance to external interference, conducive to long-distance high-fidelity signal transmission;
b, with spring locking device, reliable connection, not easy to pull off;
c, the connector specifies the signal flow direction, which is convenient to prevent errors on the connection;
The cannon plug has a male plug and a female plug, and the socket also has a male plug and a female plug. The contact of the male insert is a pin, and the contact of the female insert is a jack. In accordance with international practice, use a male plug or socket as the input end of the signal; The female plug and socket are used as the output end of the signal. Common XLR connectors are shown below:
2 car registrations
In China, it is commonly known as the lotus joint (because some types of RCA joint look like lotus petals), this joint is composed of two contacts, respectively, the hot end (level); Cold ground (-), the use of coaxial cable connection, of course, can also use multi-core audio cable, often used in general home audio equipment. Because its length is about 3.5cm, so I usually call it: 3.5cm plug.
RCA plug has male plug and female plug; Common RCA connectors are shown below:
3、TRS
Generally called stereo connector, it is composed of three contacts, respectively: head end (level); Ring end (-level); Ground, used in small headphones or laptops and other equipment on the length of about 3.5cm, but at most still used in professional audio, its length is: 6.35cm, the current professional mixer of high resistance input and plug out jack mostly use this plug, other audio equipment also mostly use this port. Common TRS connectors are shown below:
4、
Commonly known as a single tone (sound) joint, this joint is composed of two contacts, respectively, the head end (level); The Ground end. The above two connectors are used in professional audio with a length of about 6.35cm, so I usually call it: 6.35 plug. Although the TS connector and TRS connector are the same length, the appearance is very similar, but the specific function can be different, TRS stereo connector can use three cores to balance the way to transmit signals; However, the TS mono connector can only adopt non-balanced signal transmission mode. Common TS connectors are shown below:
5, speaker connector
Nowadays, 4P (4-core) professional joints and 2P (banana insert) joints are generally used, and TS mono joints or other methods are used. The common speaker connectors are shown below:
6, all kinds of converters
This type of conversion joint can be easily used to convert between different joints. Below are some common audio converter heads;
The production of connecting cables in sound systems
At present, the input and output signal modes of professional audio equipment are basically divided into: balanced mode (Balance) and non-balanced mode (Unbalance). Of course, the signal can be fed directly between balanced and balanced, non-balanced and non-balanced ports; In the case of higher requirements, between the balanced and non-balanced ports, a special converter must be used to connect to each other. However, in actual engineering, as long as the signal line is not too long and the interference is not too large, the balanced port and the non-balanced port can be directly connected to the normal transmission signal.
In a sound system, in addition to the power transmission line between the power amplifier and the speaker, the signal connection line between other devices should be transmitted in a balanced way as much as possible, which can improve the anti-interference ability of the system and increase the effective transmission distance of the signal;
1, balance and balance between the signal line
1) XLR Cannon male Joint ←→XLR Cannon female joint: This line is the most used in professional audio systems, and the production of the cannon male and female 1, 2, 3 three contacts are connected respectively, contact 1 is connected to the shield layer, contact 2 is connected to the signal hot end (pole), contact 3 is connected to the signal cold end (-pole).
2) TRS stereo Joint ←→TRS stereo joint: The production of the two TRS stereo joint between the head end (level), ring end (- level), Ground (Ground) three contacts are connected respectively. This kind of line should actually be used a lot in the sound system, but many sound engineers often use TS single-tone (sound) joints instead of the picture because of the simplicity, which should be paid particular attention to, so that a substitute signal transmission mode from balanced transmission to non-balanced transmission.
3) XLR Cannon male or female joint ←→TRS Stereo joint: The contact 1 (shielded Ground) of the XLR Cannon joint is the ground of the TRS stereo; The hot end (pole) of XLR contact 2 is connected to the head end (pole) of TRS. XLR contact 3 Connects the cold end (-pole) to the ring end (-pole) of the TRS. This is also a balanced transmission mode, which is often used in professional audio systems.
4) XLR Canon ←→XLR Canon or XLR Canon Mother ←→XLR Canon Mother: This kind of line is a little special, at most used in the signal connection between the power amplifier and the power amplifier or between the power amplifier and other peripheral equipment, the production is also to connect the 1, 2, 3 three contacts between the two joints respectively, contact 1 is connected to the shielding layer, contact 2 is connected to the signal hot end (pole), contact 3 is connected to the signal cold end (pole).
Another point is that in order to prevent \"loop interference\
2. Signal line between non-balance and non-balance
Generally refers to the TS single tone (sound) joint ←→ The signal line between the TS single tone (sound) joint and the RCA lotus joint, which is a non-balanced transmission mode, the production of the two TS single tone (sound) joint (RCA lotus joint) between the head end (stage) and the Ground (Ground) two contacts are connected respectively.
3, the signal line between balance and non-balance
XLR Cannon or XLR Cannon female connector ←→TS single tone (sound) connector, this connection mode actually becomes a non-balanced transmission mode, the XLR cannon connector contacts 1 and 3 are combined with the shielded wire and then butt the TS single tone (sound) connector Ground; XLR contact 2 Connects the hot end (pole) to the head end (pole) of the TS single-tone (acoustic) connector. In professional audio systems this cable is often used as a microphone cable in box karaoke systems.
4, speaker cable
In the connection between the power amplifier and the speaker of the professional audio system, the resistance of the speaker wire should be as low as possible, and the thick and short wire and reasonable wiring should be selected. Speaker line is common with multi-core, 50 core, 100 core, 200 core and other double-layer sheathed wire, commonly known as gold and silver wire; There are also fixed speaker cables for indoor use and cable speaker cables for outdoor movement. Speaker line is a high level high current strong signal transmission line, used for the connection between the power amplifier and the speaker. Select the speaker wire with different cores according to the need, and check whether there is a break or short circuit phenomenon.
Nowadays, professional speakers generally use four-core professional connectors, and power amplifiers generally use four-core professional connectors or 2P terminals. In terms of production, the 1 (pole) and 1- (- pole) of the four-core professional connectors of the speaker are correctly connected to the (pole) and (- pole) of the power amplifier output. There are also some speakers or amplifiers that use TS mono connectors and terminals, and the connection principle is the same. Are positive to positive, negative to negative, if the speaker will be reversed, which will affect the sound quality and stability of the speaker, while avoiding short circuit when connected, otherwise it will damage the power amplifier equipment or speaker.
In general, the above is the type of connection line we often use in the system, perhaps before we did not pay much attention to the connection of the signal line and the speaker line, taking the signal line as an example: in fact, it is as important as the blood vessels in the human body! And from the stability and long-term consideration, we must use high-quality wires and high-quality plugs, because high-quality connectors and wires have the following three characteristics:
1, with good frequency difference conduction characteristics
The connectors and wires used in ordinary audio are mostly ordinary copper, which can generally meet the requirements, and the signal distortion caused by the wire is not easy to detect. Professional high-grade audio equipment on the connection wire requirements are very strict. The most basic requirement is that the impedance is low, and the DC resistance is not particularly different from the ordinary wire, but the AC impedance and the impedance change degree with the frequency is much lower than the ordinary wire. Because the audio signal contains rich harmonic components, the higher the frequency of harmonics, the weaker the energy, the easier it is to be consumed by the conductor resistance, and these higher harmonics are the details of the sound signal timbre structure, such as the use of ordinary wire transmission, it is easy to lose and lose the higher harmonics representing the timbre details, so that the timbre lacks a sense of hierarchy and delicacy.
2, high purity connectors and wires have good high-frequency penetration
High purity connectors and wires are used to increase the diameter and surface area of the transmission line and reduce the resistance of the wire, which is conducive to the transmission of high frequency signals. Due to the skin effect of the wire, the high-frequency overtone signal flows from the inside of the wire to the outer surface during transmission. The higher the signal frequency, the more obvious the skin effect, thus increasing the impedance of the wire to the high-frequency overtone signal. The larger the surface area of the wire, the more conducive to the transmission of high-frequency overtone signals. At the same time, in order to ensure that the wire diameter and surface area of the wire are large enough, the common high-fidelity wire is made of high conductivity OFC (oxygen-free copper) multi-core wire. The higher the purity of oxygen-free copper, the better the conductivity, and of course the higher the price. The purity of OFC high-fidelity wire is generally expressed by \"N\
As agreed; As we all know, the resistivity of gold and silver in metals is the smallest, and the electrical conductivity is the best, but if gold and silver are used as the production material of fever wire, the price is very expensive, which is unacceptable to most people.
Note: \"OFC\" is an abbreviation of the English \"OxygenFree Copper\
3, small electrostatic capacity between wires
The electrostatic capacitance between wires has great influence on the loss of low frequency signal. Therefore, the dielectric constant of the dielectric material used by the multi-core wire for low-frequency signal transmission should be small to reduce its electrostatic capacitance. The insulation layer of ordinary wire is made of rubber or PVC, which not only has a large dielectric constant, but also changes with the frequency, resulting in a large low-frequency loss. High fidelity wire is best made of polypropylene PP, polyethylene PE, fluorine plastics, natural rubber and other materials made of wire insulation layer, excellent electrical performance, dielectric constant is small and basically does not change with the frequency change.
Of course, we use high-quality cables and high-quality connectors in the connection of audio equipment; We also need to ensure good quality, trouble-free welding of them. The reason for this is not to be detailed here;
Relatively speaking, I can also believe in the stability of rotten equipment, but I will not casually believe that the quality of the signal connection line and speaker line is not guaranteed! The reason, I believe everyone will understand it! (Shenzhen Yihe Audio Company)