What is the reason for the loud current sound of the power amplifier, and what happens when the powe

The current sound of the power amplifier is likely to be due to the large leakage inductance of the transformer, poor filtering, improper setting of the working point, etc., which may cause the current sound to become larger. Enclosure grounding also does not eliminate AC sounds. You can try separating the two machines with a partition to see how about it.

Elimination method for the cause of the increase in the current sound of the successful discharge:

1. Place the volume potentiometer.

If the humming sound continues, it means that the power supply filter electrolytic capacitor in the circuit is reduced and desoldered, then the same component should be replaced, or the filter capacity should be increased.

2. If the buzz is loud as the volume increases, it means that the noise is ** in the preamp, the first thing to do should be to unplug the audio source input wire, and then turn the volume up, if not, it is the audio input shielding wire.

repairs or replacement of audio cables will do.

3. Check whether the audio input shield cable is connected properly.

The current sound of the power amplifier is relatively loud, and the following methods are used to eliminate it. First of all, turn off the volume potentiometer to the minimum, at this time there are two situations of hum: 1. The hum still exists, indicating that there is a fault in the power supply circuit of the speaker, please check whether the rectifier diode in the power amplifier circuit has breakdown or short circuit, otherwise replace the same type of diode.

The second is whether the filter capacitor is open, the capacity is reduced or fails, otherwise the capacitance is replaced and increased. 2. The hum is gone, as the volume increases, the hum is also loud, at this time, it should be operated like this: unplug the audio input line first, if the hum is gone, it means that the fault is in the audio input line, check whether the audio input line has poor contact and the ground terminal is broken.

If the hum continues, then there is a problem with the pre-amplification circuit in the amplifier, and the amplifier should be turned on for repair. If you can't fix it yourself, ask the master to troubleshoot.

Generally, it is the older power amplifier that is prone to the problem of high current sound. This type of fault is difficult to troubleshoot. There are generally several reasons for this:

First, the power transformer is aging, the magnetic flux leakage increases, and the interference circuit is interfered with;

Second, the power transformer has a slight short circuit, and the secondary AC voltage is low;

Third, the rectifier pipe has a broken down bad pipe, which increases the AC component;

Fourth, the filter capacitor capacity is reduced or there is soft breakdown;

Fifth, the power amplifier pre-amplification circuit or signal line is too close to the transformer;

Sixth, the shielding effect of the input signal line is not good.

The current of this power amplifier is very loud when the horn is energized, and the main filter capacitor is broken after detection, and it works normally after replacement.

1.Determine whether it is electromagnetic interference.

Electromagnetic interference is mainly divided into power transformer interference and stray electromagnetic waves.

Interference. Power transformer interference: due to the power supply magnetic flux leakage, the effect of installing a shield cover for the transformer is very obvious when conditions permit, which can block the magnetic leakage to the greatest extent, and the shield cover is best made of iron material (the shield must be grounded).

In addition, using an external transformer is also a good solution.

Spurious electromagnetic interference: It is common for speaker wires, crossovers, wireless devices or computer hosts to become sources of interference. Keep the main speaker as far away from the computer as possible and reduce the number of peripheral wireless devices.

2.Whether the various wiring are in good contact. There can be no broken wire or the wire is in contact with the power amplifier shell, do not tie the wire together with a trapped wire, use the best wire, and tighten (or weld firmly) the wiring place.

3.If there is a communication sound when the audio input is not connected or the input plug is not plugged in, it is usually a problem in the machine. Problems in the machine are first checked for the filter circuit.

Whether it is effective or not can be measured by measuring the filter capacitance.

capacity or in parallel.

The same capacitance method to test. Replacing a good capacitor can solve this problem.

4.Another point is that the shielding layer of the shielding wire from the audio input socket to the power amplifier input should be grounded at one end, and do not use its shielding layer as the low end of the signal to transmit the audio signal, otherwise it is easy to produce AC sound.

5.The current sound of the amplifier may be due to the poor contact between the input circuit of the amplifier and the previous circuit. For example, volume potentiometers.

Loose grounding terminal, poor grounding of the housing, broken common end or poor contact of the signal line between the pre-stage and the post-stage, etc. Of course, the excessive quiescent current of the final power amplifier tube of the ordinary power amplifier circuit will also cause current sound.

<>1. Because the clutter filter of the transformer output power supply in your subwoofer is not clean, the horn produces a humming sound, which is the so-called "AC sound". If you have strong hands-on ability, you can get better results by connecting a larger capacitor in parallel at the place where the transformer output has been rectified (pay attention to the polarity and withstand voltage value).

2. If the above methods can't solve the problem, it means that the magnetic flux leakage of your transformer is more serious, and the electric field caused by the alternating magnetic field produces a humming sound in the horn. You can use a thin copper sheet to carefully wrap the core of the transformer, and it's OK, or you can use aluminum foil, but the effect is not as good as copper foil.

3. Take a look at your input socket, if the grounding position (the metal outside the lotus socket) is not open and soldered, you can find a small porcelain capacitor and connect it between the input (the middle of the lotus socket) and the grounding.

4. As soon as the active speaker is turned on, the subwoofer emits a huge "buzzing" sound, which is due to the fact that this is a problem with the audio circuit, and there is no circuit in the audio to filter out the pop-noise generated by the boot.

At the moment when the speaker is turned on, there is a large DC current through the speaker to produce a loud noise. There should also be noise in the two small speakers, but the reason for the frequency attenuation is very small. Here's how to fix it:

Replace it with a better speaker, or plug in a voltage regulator for the speaker.

First of all, figure out the speakers.

If there is a "hum" sound, it is caused by the change of the capacity of the electrolytic capacitor in the filter circuit of the power amplifier, or the capacity is too small; If the sound is loud and there is a loud "buzzing" sound, it is caused by the poor shielding of the audio input of the power amplifier.

2. The shell of each element must be grounded, and the audio input line must be shielded.

3. The horn has a "hissing" sound, and most of the cases encountered in this case are caused by poor overall shielding, or the primary stage of the power transformer winding is not well isolated. If it doesn't work, connect two 4700p capacitors with a working voltage of 250V in series at the power input end (the power input end of the transformer), and the center tap is grounded, which can also reduce the noise.

The cause of the sound of electric current is generally electromagnetic interference.

Mechanical noise, heat dryness, etc. Otherwise, the card is not properly inserted, the active speaker input is terminated on the speaker output of the sound card, or the sound card driver.

problems. It can be said that it is possible to cause such a situation, both software and hardware.

1. Mechanical noise is unique to active speakers. During the operation of the power transformer, the core vibration caused by the alternating magnetic field will produce mechanical noise, which is very similar to the fluorescent lamp ballast.

The buzzing sound that comes out. Choosing the best product is still the best way to prevent this noise. In addition, we can add a rubber shock absorber between the transformer and the fixing plate.

2. If the potentiometer is used for a long time, the contact between the metal brush and the diaphragm will be poor due to dust accumulation and wear, and noise will be generated when rotating. If the screws of the speaker are not tightened, and the inverter is not handled properly, mechanical noise will also be generated when the **big dynamic**.

This thermal noise can be dealt with by replacing low-noise components or reducing the working load of the components, and reducing the operating temperature is also one of the most effective methods.

3. Electromagnetic interference can be mainly divided into power transformer interference and stray electromagnetic waves.

Interference. The power transformer interference is caused by the magnetic leakage of the power supply of the multi-speaker speaker, and the effect of installing a shielding cover for the transformer is very obvious when conditions permit, which can block the magnetic leakage to the greatest extent, and the shielding cover can only be made of iron materials.

There are many reasons why the amplifier has communication sound, mainly the following points, which should be overhauled in line with the easy and then difficult method:

The first is to check whether there is a problem with the audio cable, such as the plug and socket are not connected properly, and the internal aging of the audio cable has poor contact. It's a good idea to replace a pair of audio cables and see how it goes.

The second is to check whether the speaker wire has oxidation, rust and poor contact of the joint.

The third is whether the connector of the internal connection line of the power amplifier is loose and has poor contact, or the circuit board is not well grounded, or the circuit board is too dirty, and leakage occurs after being wet.

Fourth, the leakage of the capacitor on the power amplifier board leads to the leakage of the circuit board.

Fifth, the performance of the filter capacitor of the power supply is poor.

Sixth, it is caused by the virtual welding or damage of the welding leg of a certain component on the power amplifier board.

What is the sound of "electric current"? The electric current is silent.

You're talking about noise. This should be overhauled to see what causes it and prescribe the right medicine.

Poor filtering of the power supply and unreasonable circuit design can introduce noise.

Generally, the "power supply" is not clean. When the potentiometer is turned off, there is no input signal, and there is no output without input. Indicate that the noise source is in the preamp.

It may be a problem with the sound source, so use your mobile phone to see the sound source.

Offensive and defensive noise is an old problem, and it is mainly a problem of circuit design. Disconnect the preamp first to listen to see if the noise is coming from the preamp. Then there is whether the power transformer has electrostatic shielding?

Try four capacitors in parallel on the bridge rectifier diode (the capacitor is best to use a metallized capacitor), the pre-signal line is far away from the power supply part, and then there is a "little grounding", the shielding layer of the audio input interface, directly soldered to the grounding point of the filter capacitor! Also, you can try grounding one end of the shield wire, etc., in short, trial and error will be effective, which requires patience.

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It should be interference caused by poor grounding. If you look at whether the shell cable of the audio signal cable is in good contact with the amplifier shell, it can usually be solved by changing the cable.

Grounding is a key issue for power amplifiers, choose a little grounding to avoid grounding loops, and the quality of transformers and power supplies will also bring current sound.

In your case, it's probably a grounding problem.

1. The grounding screw inside is loose, 2, the ground wire is broken on the side of the small signal, and see if the small black cable is loose and taken off.

3. It is also possible that the main power supply part, the large capacitor is broken, causing the main power supply ripple to be too large.