Five common failures of professional sound systems

Five common failures of professional sound systems

At present, there are many types of professional audio equipment, and the replacement is also changing with each passing day. So many equipment in use will inevitably have some kinds of failures, some are the failure of the equipment itself, and some are caused by improper use by our sound engineers. Generally speaking, the types of sound system failures can be summarized into five categories: power failures, line failures, human operation failures, equipment failures, and interference failures.

 

Audio system power failure

 

● The overall power configuration of the audio system is very important. The following points should be noted:

 

Three-phase power supply: Generally, places that use professional audio equipment will apply for the installation of three-phase power supply. Two independent three-phase power supplies are also used in more important places. If one of them fails, the entire system will not be paralyzed.; Even in very important places, backup power supplies such as "UPS" such as computers are used, which shows the importance of power supplies.

 

Independent sound and light power supply: It is best for sound and lighting to have their own power supply, otherwise one is susceptible to interference and the other is not safe to work.

 

Total power distribution: It is not enough to have a powerful power supply, but also pay attention to the distribution of the power supply; In principle, the mixer and various audio source equipment should have independent power supply; There must be at least 2 independent power supplies. Each independent power supply is controlled by a corresponding air switch, so it is very convenient for us to switch devices.

 

Faulty wiring of the sound system

 

● Power line failure: there are many places where power supply is used in the audio system, and various power lines need to be connected, such as: mixer and audio player and other power supplies, peripheral equipment power supplies, power amplifier power supplies, stage power supplies, active speaker power supplies, video system power supplies, etc., there are many components that need power supply in one place, so the power supply line should be safe and reliable, and try to avoid failure.

 

Signal line failure: If the sound system is compared to a person, then the signal connection line of the audio system is like the blood vessels of the human body, and the quality of "blood circulation" directly affects the stability of the audio system.

 

 

There is a problem with the connection between the amplifier and the speaker: everyone pays more attention to the connection between the amplifier and the speaker, and uses a good quality and thicker speaker cable. If the speaker cable fails, it is usually a short circuit. Now the speakers are 6.35 plugs, so the risk of short circuit of such plugs will be greatly increased; the speaker wire is rarely open, so if the thick wire is open, it is generally man-made. It is unlikely that this is a problem with the wires themselves.

 

Human operation failure of the sound system

 

● "Technology is people-oriented", not bad at all. No matter how good and advanced the equipment is, someone must operate it. Of course, people make mistakes. Therefore, some operating errors in the sound system are inevitable. We can only study hard, strengthen ourselves, hone ourselves, accumulate more experience, and try to avoid failures caused by such human errors.

 

Signal connection issues:

 

1. Connection between audio source playback equipment and mixer: all kinds of CD, DVD, MD, deck, etc. should be connected to the mixer with supporting cables, and generally inserted into high-resistance ports.

 

2. Dynamic microphones, condenser microphones and other general plug-in XLR low-resistance ports. However, the signal of the wireless microphone is amplified by the receiver, and it takes experiments to know which end is suitable for insertion.

 

3. In principle, the signal output by equipment such as frequency bands should be connected to high-impedance ports, but if the line is long and the interference is large, it can also be connected to low-impedance signal ports.

 

Device control issues:

 

There are many kinds of audio equipment, and our audio engineers need to make adjustments to each one. What we call human operation errors mainly occur in the process of performance, such as silent, staccato, feedback, noise, etc.

 

1. Channel level attenuation switch of the mixer: Some mixers add a level attenuation switch of about 20dB before the gain knob. When a sound source such as a CD is input from a high-impedance port, due to the high level, it is appropriate to press this switch to attenuate the audio signal by 20dB.

 

2. Mixer gain adjustment: Some sound engineers do not know the importance of channel gain, adjust the knob indiscriminately, sometimes turn off the gain knob, and even press the 20dB-level attenuation switch at the same time, think about how small the sound will be at this time?

 

3. Adjustment of the equalization group of the mixer: As the name implies, the mixer is mainly used to adjust the timbre, and the adjustment of the timbre mainly depends on the equalization group. It's simple to say, nothing more than high bass plus a couple of corresponding frequency selection knobs. Although the sound may not be very good under normal operation, there will be no performance accidents. However, some sound engineers sometimes boldly turn the balance knob. If the bass increases too much, it will greatly increase the burden on the entire amplifier and speaker, which may damage the equipment and the sound is easily distorted.

 

4. AUX adjustment of the mixer: Our AUX is mainly used to send signals to the effect. In the mixer, if we send a signal effect from the AUX6, after the effect processing, if we output 2 signals to the mixer 23-24 channels of the mixer, then do not open the AUX23 knob of the two channels 24-6 at this time, otherwise the signal will flow back to the effector after just being processed by the effector.

 

5. Audio and video of the mixer: The audio and video knob is usually considered an optional thing, but we must pay attention to the audio and video when using the left and right output volume of the total output. If you use the total output right output signal, but the audio and image of the mixer channel are hit to the left, it will cause a silent failure, which needs attention.

 

6. Mixer monitoring and mute switch: Under normal circumstances, the mixer monitor and mute switch are close together. Be sure to see clearly when operating. If the mute switch is pressed by mistake when the monitor switch is pressed, it will also cause a silent failure.

 

There is a problem with the device itself

 

● If it is a real failure of the device itself, it is considered a "hard fault". For example, if the amplifier is broken, the horn is broken, that's a maintenance engineer. The scope of our sound engineers' work is to match the sound system and adjust the various sounds. There is no need to do all kinds of martial arts. Master!

 

Interference failures

 

● Find mixer interference sources: Most mixers will have a 48-volt phantom power supply, which can be used to drive various condenser microphones, but because it is the current transmitted by the microphone line, it is necessary to check frequently to ensure that the microphone line is unblocked, otherwise a large current impact sound will be emitted when the line is in poor contact.