First, the connection of the mixer

The input signals of the mixer can be roughly divided into two types: low-resistance microphone signal input and high-resistance line signal input. Only after distinguishing between high resistance and low resistance can the correct wire be selected for the corresponding connection. Generally speaking, the input sockets of the mixer can be basically divided into three types:

1, TRS: The high impedance input part usually uses 6.35cm TRS stereo connector to balance the input, and try not to use 6.35 TS tone.

(Acoustics) Interface is used for unbalanced input. The output signals of most audio playback devices such as CD, VCD, DVD, MD and MP3 and most musical instruments are usually high impedance signals.

2.XLR:XLR cannon connector is usually used as a balanced input with low resistance. At present, most wired microphones are usually connected to the mixer with low resistance sockets.

3.RCA: If there is a mixer with recording input, it is generally connected with RCA Lotus connector. Problems needing attention in the signal input part of mixer: As mentioned above, the input signal of mixer can be roughly divided into low resistance input and high resistance input, but how to accurately define whether a signal belongs to low resistance or high resistance requires flexibility. For example, according to the standard, electronic organ, electric bass, electric guitar and so on. It is a high impedance signal and can only be input into the mixer with a 6.35 plug. However, in some places, the connecting line from the stage to the mixer is too long, and the line resistance is large. Coupled with the interference of lighting and other systems, the background noise of this signal line is already very large. Even if there is no sound source signal input, increasing the gain of this line input channel on the mixer will have great background noise.

Wiring of the output part of the mixer:

There are many sockets in the output part of the professional mixer, each with its own division of labor, unlike the input part, although there are many sockets, it is relatively simple. Therefore, be careful when connecting the output signal. Usually, the main output parts of the mixer still refer to total volume output, grouped volume output and auxiliary output. Generally speaking, the output part of the mixer can be divided into six parts according to the function:

1. Grouped output: If we control the volume of the woofers individually by grouping the woofers into 1-2, then we can only output audio signals from the corresponding output jack of the mixer 1-2. Most of the output ports of grouped output use TRS stereo sockets for balanced output, and of course some use Cannon sockets.

2. Main channel output: The L-R main channel usually adopts XLR Cannon balanced output, and some small mixers are also replaced by TRS stereo jacks.

3. Auxiliary output: The auxiliary output in the mixer is most commonly used to output to the voice effect device, followed by providing monitoring signals for bands or singers. Of course, it also has other uses, such as recording, as an auxiliary speaker signal. AUX usually uses TRS stereo jack to output signals.

4. Direct output part: The professional mixer also has a "direct output" socket in each input channel, which can be provided to other devices for recording and monitoring. Each channel of the mixer usually uses TRS stereo socket to output signals. For example, if there are 20 audio signals, we can input them into the mixer of the TV station first, and then use the Direct output jack in the mixer of the TV station to input them into the mixer of the live performance. Now, of course, for the sake of safety, these 20 sound source signals are adjusted and distributed through the signal amplification distributor, and then sent to the TV station mixer, live performance mixer, standby emergency mixer, recording mixer or other equipment respectively.

5. Recording output: RCA Lotus connectors are mostly used for general analog recording output signal sockets. If it is a digital signal, other digital output modes such as optical fiber and firewire can be used.

6.INS plug-in socket: this socket in the mixer is connected between input and output through TRS stereo connector. Many sound engineers may not know how to insert ins. They can plug peripheral devices into the input channel, grouping channel or main channel (left channel and right channel) of the mixer, and independently process the sound signals of the inserted channels. When using, use TRS big three-core stereo connector to connect. The method is to output a signal from the head end of TRS big three-core stereo plug and connect it to the input end of the equipment to be inserted, and then send a signal from the output end of this equipment to the ring end of TRS big three-core stereo plug, and then flow into the mixer. In this way, an equalizer is inserted into microphones 1 and 2 of the mixer, which is equivalent to cutting off the water pipes of microphones 1 and 2, adding a water processor (equalizer) and inputting it into the mixer, so that the timbre adjustment effect is better. The above is the connection of the mixer. Whether it is the input part or the output part of the mixer, the sockets and signal connection methods used are basically these kinds, but attention should be paid to the correctness when connecting.

Second, the equalizer connection:

Equalizer: As we all know, the main function of equalizer is to adjust timbre, adjust sound field and suppress acoustic feedback. Therefore, the equalizer is almost an indispensable equipment in the current sound system. At present, the balanced input and output parts are all balanced sockets. It is best to use the balance circuit of XLR connector when connecting, and of course, the balance circuit of TRS connector can also be used.

Third, the power amplifier and speaker connection:

Special attention: in terms of signal, the signal lines of the power amplifier should be balanced as much as possible to minimize noise. Many sound engineers like to provide one or two signal lines for multiple power amplifiers. However, if there are more than four power amplifiers, it is suggested to use signal amplifiers to divide enough signal lines without attenuation for each power amplifier, which can reduce system noise, reduce hidden dangers and improve signal-to-noise ratio. In terms of power transmission, try to use thick and short speaker wires, adopt reasonable wiring, shorten the distance of speaker wires, pay attention to positive and negative poles and avoid short circuit.

Problems needing attention in connection of power amplifier equipment;

1, pay attention to power supply: audio equipment should have a dedicated power supply, which should be separated from the power supply of lighting. Lighting likes lower voltage, but audio needs standard voltage. With a dedicated power supply, there must be a stable and reliable power socket, and try to use the "power sequencer". Although the cost has increased, the stability and ease of use have improved. In short: it is very important to connect the power supply of all audio equipment correctly and firmly. One more thing to note: some imported equipment will have 1 10V and 220V selector switches in the power supply section. In China, you need to confirm your choice.

220V position can only be connected with power supply.

2. Pay attention to the grounding of the equipment: It is very important to connect the grounding wire correctly to all audio equipment. Good grounding can reduce the interference of equipment signal transmission and improve the stability of equipment. It should be noted that the grounding wire should be made according to the grounding standard of lightning protection wire, that is, the conductor buried underground should be rust-proof, have good contact and be buried deeply, and must not be used together with the grounding wire equipped with three-phase power line, which will not only reduce the noise in the audio system, but also easily damage the equipment.

3. Pay attention to selecting the appropriate connection signal line: an audio device, we can connect it with XLR cannon balance line instead of TRS balance line; If you can connect TRS balanced line, don't connect TS mono unbalanced line; Only when there is really no way can the TS mono unbalanced line be used to connect the equipment.

4. Pay attention to signal phase inversion and short circuit: short circuit of signal line often causes silent fault, but it is very troublesome to check, unless the signal line is removed and tested by multimeter, so be especially careful when bonding wires.

5. Pay attention to the length of signal wire: when connecting equipment, try to use a shorter signal wire to save costs and reduce line resistance and interference. In general, the longest signal line of balanced transmission mode can reach about 300 meters, while unbalanced line cannot be used for long-distance transmission.

6. Pay attention to the level of the equipment: If there are +4 and-10 or -20 level switches on the back panel of the equipment, we usually put them in the position of +4, which is the standard level.

7. Pay attention to through: Many devices have bypass buttons, which are generally not acceptable. Check this button, or the equipment behind the voltage limiter will lose its protection function.

8. Beware of misoperation: Because there are many devices and buttons, misoperation often occurs. For example, some electronic frequency dividers have a "× 10" button, so don't press it easily. For example, if the intersection is adjusted to 200Hz, if you press this button 200× 10, it will become 2000Hz, so be sure to avoid misoperation. With good equipment and correct and reasonable connection, the effect of this sound system will be perfect!