Completely different from the RCA terminals that analog audio cables directly transmit sound, the XLR terminals are balanced analog audio connectors: analog audio cables transmit sound directly, and the Balanced Analog Audio interface uses two channels to transmit signals with the same signal but opposite phases; receive The terminal equipment subtracts these two sets of signals, and the interference signal is cancelled out, thereby obtaining a high-quality analog signal.
XLR connectors are the most widely used connectors in professional audio systems and can be used to transmit various audio signals in audio systems, such as microphones. Generally, the balanced input and output terminals are connected by XLR connectors. The advantages are as follows:
a. The balanced transmission method is adopted, which has strong anti-interference ability, which is conducive to long-distance transmission (not more than 100 meters).
b. With a spring locking device, the connection is reliable and not easy to pull off.
c. The connector specifies the signal flow direction, which is convenient to prevent connection errors.
XLR plugs are divided into male and female plugs, and sockets also have male and female sockets. Male contacts are pins and female contacts are jacks. According to the international common practice, the male plug or socket is used as the output end of the signal; the female plug and socket are used as the input end of the signal. According to the number of contact pins of XLR connectors, the main types of XLR connectors on the market are as follows:
1. XLR-3: 3-pin XLR head, microphone cable, is the most commonly used and earliest product, and is also the standard balanced signal in the audio industry. Due to the low cost of XLR-3 and the convenience of zero-time emergency response when the line is missing on site, lighting manufacturers also use 3P XLR connectors; because the XLR-3 connector can support a normal current of 15A, and has the ability to obtain a normal life. Features, 3P XLR connector is also selected as the charging connector for electric bicycles/electric wheelchairs in Europe.
2. XLR-4: 4-pin XLR head. Wide range of uses: intercom headphones, two of which are used for mono headphone signals and two pins for unbalanced microphone signals; DC power connections for broadcast cameras and related equipment; some mixer lights interface.
3. XLR-5: 5-pin XLR head. Generally used for standard DMX512 digital lighting control, output two DMX channels simultaneously on 5-pin.
4. XLR-6: 6-pin XLR head. Used for: dual-channel internal intercom system; some manufacturers' LED lamps will use 6P XLR connectors to send RGB three-color different currents.
5. XLR-7: 7-pin XLR head. Used for: Remote control connections, such as Le Maitre and Ultratec fog machines; sometimes as a pre-quick connection for 3-way systems.
