How to avoid communication sound when LED display audio equipment is connected?

How to avoid communication sound when LED display audio equipment is connected?

 

 

 

 

 

If you don't avoid the current sound, then no matter how good the sound quality is, how to avoid AC sound when the LED display audio equipment is installed and connected?

 

1. The shell of reasonable grounding audio equipment is generally connected with the power transformer shield of the equipment, and the shell of this equipment also has a "ground", which is also different from the other two "grounds". When the "ground" of the earth is more disturbing, the "ground" of the device shell can be connected to it to reduce the AC noise interference, and vice versa.

 

2. The power supply of the weak signal equipment and the power supply of the strong signal equipment are connected in groups with the same set of power supply of the weak signal sound source equipment such as CD, card holder, effect, mixer, compression limiter and equalizer, and the strong signal power amplifier is connected with another group of power supply, which can avoid the AC noise interference of the power supply in the conduction mode;

 

3. Separate the signal ground between two audio equipment with different "ground" potentials to avoid direct communication of the equipment or the formation of a ground loop. For example, the balanced connection outer shield wire is only grounded at one end, or neither end is grounded, etc.;

 

4. When connecting a clean power supply to power supply, a separate power transformer should be designed; When unconditional, it can be powered by an independent set of power supplies, which can be supplied separately from air conditioners, lights and other equipment; Or use isolated power transformers, etc.

 

5. The use of suspension grounding means that the potential of the point is the same as that of the ground, which is zero potential. However, the point is not directly connected to the ground. It is the point at which the potential of the audio equipment circuit to ground is zero. There is an impedance between this "ground" and the actual ground, and it is a high impedance, which can overcome common-mode interference;

 

6. There can be no DC circuit connection between the two audio equipment;

 

7. The connection of different systems shall be connected by balanced isolation transformer to connect the audio system with the audio system of the TV broadcast vehicle; Connection of the system to a large electronic display; or the connection with the electronic computer, etc., generally must be connected with a balanced isolation transformer. The co-location of different systems is easy to cause the interference of AC noise;

 

8. The long-distance transmission signal can be transmitted by balanced or balanced isolation transformer, and the short-distance transmission can be unbalanced. The transmission mode of balanced isolation transformer is generally balanced transformer at both ends, and one end of the shield layer is grounded, or it can be suspended without connection. Grounding can play a shielding role and also prevent electric shock accidents caused by equipment leakage. When it is not grounded, the balance transformer at both ends can play the role of insulation isolation, and the center of the balance transformer is grounded, which can dissipate static electricity;

 

9. In the case of serious power supply interference, the equipment is connected in phase to connect the small signal audio equipment and the power supply of the monitoring equipment together, and the one phase with small AC sound interference in the three-phase power supply is selected, and the other two phases are connected to the large signal power amplifier, which can reduce the AC noise interference from the power supply;

 

10. Check if your grid power supply is not clean;

 

11. Is it a grounding problem for some equipment;

 

12. The second is to see that there is no interference between the equipment connections (it is very messy/whether the interface is soldered);

 

13. Check whether it is interfered by lights (silicon box, signal line);

 

14. Usually the sound of communication is louder, it is the problem of the power amplifier, and if the signal-to-noise ratio of the power amplifier is not very good, it will make a very loud sizzling sound. Check whether it is a problem with the signal line, as long as you unplug all the signal lines and then turn on the power amplifier, if there is no loud AC sound in the speaker, it is a problem with the signal line, first see if the plug has a short circuit and touches the line (take the multimeter to measure more accurately), if there is it, you can re-solder the plug. If that doesn't work, then the only way to do that is to change the signal cable again. Unplugging the signal line and there is still a very loud communication sound, that is the problem of the power amplifier, indicating that the power amplifier is relatively poor, and the only way to solve this problem is to change the good power amplifier.