How to solve the common faults of multimedia speakers

Many users don't pay special attention to the use of multimedia speakers. Due to the strangeness of product structure and the lack of relevant knowledge, they often make do with the speakers after they have a small fault. They really can't replace them again. In fact, many problems of multimedia speakers are easy to repair, which can be easily handled by ordinary users.

1. When adjusting the volume, there will be a crackling sound. When the volume is large, it will be small.

this is the most frequent failure in the multimedia speaker. I believe that many users have this experience. After a period of use, adjusting the volume of the speaker often occurs this situation. Many users choose to use the volume adjustment of computer system to adjust, which is undoubtedly a kind of expedient.

in fact, as long as this happens, it can be judged that there is a problem with the phaser that adjusts the volume. Most speakers use potentiometers to change the strength of the signal (except for digital tuning potentiometers), so as to adjust the volume and subwoofer. The potentiometer, on the other hand, changes its position on the carbon resistor through a movable contact, so as to change the resistance value. With the increase of use time, there will be dust or impurities falling into the potentiometer, and the contact of the potentiometer may also be oxidized and rusted, resulting in false contact. At this time, when adjusting the volume, there will be "crackling" noise.
solution is relatively simple, just need to replace a new potentiometer is enough, its cost will not exceed 2 yuan. However, the simplest way to deal with it is to turn on the speaker, and then turn on the four pressing tabs behind the potentiometer to expose the movable contacts of the potentiometer. Then, clean the carbon resistor with anhydrous alcohol, drop a drop of oil on the carbon resistor, and finally install the potentiometer in the original position to solve the noise problem.
of course, the above is what most people will encounter. But there's another reason for this: the quality of the potentiometer is not stable. In use, the reed of the left and right channels was originally separated, but now because of the dislocation, it is on and off during use, which produces the noise of "Thunderclap". It's also very simple to deal with this. We just need to use pointed nose tweezers to gently pull it out and then install it in place.

2. The sound can be played normally, but the "crackling" noise will be heard from time to time.

some users may have this situation, when using the speakers, they will make "crackling" noise irregularly, but when using headphones, it is very normal. And the noise of the speaker is sometimes longer, sometimes shorter, but then it is normal. At the beginning, it was also suspected that the audio signal plug was not in good contact, but it was also unplugged again, and the problem was not solved after the cable was replaced.
In fact, the root of this problem lies in the power socket. A poor quality power socket has poor quality and elasticity of phosphor copper sheet used inside. After long-term use, it will lead to poor contact, one time contact, one time disconnection. At this time, the power supply of the box will be on and off for a while.
and there is a large capacity filter capacitor inside the power supply, which will cause the power supply voltage of the power amplifier circuit to be high or low. Therefore, the intensity of the sound it makes changes significantly. At the same time, because at the moment of on-off, there will be current on-off interference signal into the amplifier circuit, which will cause other noises, that is, the "crackling" sound you hear.
The solution of emsp is simple: replace the power socket with a new one of good quality. Some profiteers may use the reasons that customers don't understand to demonstrate to customers that the speaker has been repaired and the money is collected. We all know this. We should not be fooled easily in the future.

3. The sound plays normally, but one speaker is loud and the other speaker is quiet.

If you use your hand to break the volume potentiometer to one side, the volume of the two channels will be the same. This fault is similar to that on the previous page, and it is also the problem of volume potentiometer. Because the left and right channels of the volume potentiometer are independent. Because the reed has been used for too long, the spring inside is too weak to contact the carbon resistance closely. This is also relatively simple. Adjust the reed by hand.

4. There is sound, but only high pitch, but no low pitch.

this kind of fault is generally because the volume of the speaker is too large, so after a long time of use, the subwoofer is burned. This is very normal, like bass friends think the greater the better. Some friends can even turn it very high, and the volume is also turned to more than 70%, which is the easiest way to burn the bass. Generally, 30% - 50% volume and 30% - 40% bass are recommended. In addition, the thread may be broken. In this case, you just need to pay for a new thread.

5. There is sound, but the sound is not clear and the specific content cannot be heard clearly.

this kind of fault may be not only the damage of tweeter, but also the break of signal line, or the damage of integrated block of tweeter amplifier. In addition, it should be noted that if you use a sound card, sometimes you may accidentally change the settings, so that the speaker can only hear the female voice, while the male voice cannot.

6. As soon as the machine is turned on, the "buzz" will ring directly. No matter how the volume is adjusted, the noise cannot be eliminated.

this situation is generally due to long-term use, plus the speaker is closed, the heat can not be dissipated. Therefore, the internal temperature is too high, resulting in the power amplifier integrated block overheating and damage. In fact, all the genuine power amplifier integrated circuits have the function of temperature protection. When it overheats, the power amplifier integrated circuit will automatically stop output; when the temperature drops, it can automatically resume work.

5. There is sound, but the sound is not clear and the specific content cannot be heard clearly.

this kind of fault may be not only the damage of tweeter, but also the break of signal line or the damage of integrated block of tweeter amplifier. In addition, it should be noted that if you use a sound card, sometimes you may accidentally change the settings, so that the speaker can only hear the female voice, while the male voice cannot.

6. As soon as the machine is turned on, the "buzz" will ring directly. No matter how the volume is adjusted, the noise cannot be eliminated.

this situation is generally due to long-term use, plus the speaker is closed, the heat can not be dissipated. Therefore, the internal temperature is too high, resulting in the power amplifier integrated block overheating and damage. In fact, all the genuine power amplifier integrated circuits have the function of temperature protection. When it overheats, the power amplifier integrated circuit will automatically stop output; when the temperature drops, it can automatically resume work.

7. The sound played by the computer is normal, but after a period of use, it makes a "buzz" sound, which can't be tolerated by the ears.

The fault of emsp is similar to that of the sixth case, but the integrated circuit of the power amplifier has not been completely damaged, only when it is overheated. We can open the case and increase the area of the power amplifier integrated circuit. Of course, you can also replace the heat sink with good quality.

8. Turn on the power switch of the speaker. The speaker does not sound "bang" when it is normally turned on. Turn on the music playing software to adjust the volume, and there is no sound in the speaker.

this kind of fault is also common: there is no sound in the speaker after power on. Does this mean that the speaker is broken? How to judge? First, turn the volume potentiometer to the maximum position before powering up the speaker. Then, when turning on the power switch, pay attention to whether the speaker has a "bang". If yes, there is no problem with the speaker, and the power supply is good. Then, no sound may be the driver error or sound failure of the sound card, or it may be muted or the volume is too low. Moreover, the signal wire plug is not properly connected, or the signal wire is broken.
in addition, the use time of the speaker is too long, and the internal temperature is too high, which causes the temperature fuse in the power transformer in the speaker to blow, which will also cause the above fault performance. Don't worry, we don't have to replace the power transformer. As long as you carefully remove the transformer, observe the primary coil of the power transformer from the outside (that is, the end connected with 220V electricity) to see which side is convex. On the convex side, carefully remove the plastic film on the surface with pointed tweezers, and you will find a small white square with the words "250v2a", which is the temperature fuse resistance. If the use time is too long and the temperature of the transformer is too high, then in order to prevent fire, the fuse resistor acts to cut off the current supply. We just need to short-circuit the two ends of the fuse resistor directly, but we need to pay attention to heat dissipation in the future use, and do not use it for too long to ensure the safety of the equipment.