Fault Analysis Of Speaker System

- Jun 19, 2018-

The speaker system is one of the important components of the audio equipment and is usually composed of a speaker, a frequency divider, a cabinet, and a sound-absorbing material. The speaker system has a lower failure rate and fewer types of faults. Common faults fall into the following four categories.

 

First, silent.

1. The speakers are disconnected or the divider is abnormal. When the speaker cable is broken, the speaker unit has no excitation voltage and silent failure occurs. The divider is generally not easy to break, but it may cause failures such as the disconnection of the lead connector and the frequency division capacitor.

2. The voice coil is broken. You can use a multimeter R×1 file to measure the speaker lead wire. If the resistance value is , use a knife to scratch off the seal of the two ends of the voice coil, and then test the bare copper wire. If it still does not pass, it means that the voice coil inside Broken wire; if the measurement has been through and there is a " crackling" sound, it shows that the voice coil lead breaks, can be a good solder on the end of the line, and then another section of the enameled wire similar to the voice coil winding can be welded.

3. Broken speaker leads. Due to the frequent vibration of the speaker cone, the braided wire is easily broken and sometimes the wire is broken, but the cotton core wire remains connected. This kind of braided wire is not easy to buy and can be replaced by a slightly longer flexible wire.

4. The voice coil burned. Use a multimeter R×1 to measure the speaker lead. If the resistance is close to 0Ω and there is no “tick” sound, the voice coil is burned. Before replacing the voice coil, you should first clear the debris in the magnetic gap, then carefully place the new voice coil in the magnetic gap, correct the voice coil, while listening to use the strong glue to fix the upper and lower position of the voice coil, until the best voice coil After the position, use a strong glue to fill the gap between the voice coil and the cone to about half, and finally seal the dust cover. Put the speaker cone up and use it for a day.

 

Second, sometimes there is no sound.

1. Bad speaker wire. Normally, the voice coil leads are broken or soldered. When the cone vibration is frequent, the break point is turned on and off. It will not ring when there is no regularity.

2. The voice coil lead is broken or short-circuited soon.

3. The power amplifier output jack is bad or the speaker input cable is disconnected.

 

Third, the volume is small.

1. The speaker performance is poor and the magnetism of the magnetic steel is decreased. The sensitivity of the loudspeaker depends mainly on the magnetism of the permanent magnet, the quality of the cone, and the pros and cons of the assembly process. You can use a ferromagnetic object to touch the magnetic steel, and roughly estimate the magnetism of the magnet according to the attractiveness. If the magnetism is too weak, you can only replace the speaker.

2. The magnetic core is loose. When the magnetic core of the speaker is loose, it will be attracted to the side by the magnetic plate, which will make the voice coil be squeezed and hinder normal sounding. During the inspection, tap the paper cone by hand. If you do not press it, it may be that the voice coil is pressed by the stem and it must be removed and re-fixed before it can be used again.

3. The frequency divider is abnormal. When there is a bad component in the divider, the signal of the corresponding frequency band is blocked, and a small volume sound of the speaker occurs in this frequency band. It is important to check whether the crossover capacitor connected in parallel with the subwoofer is short-circuited and whether the crossover inductor connected in parallel with the tweeter is short-circuited across the layer.

 

Fourth, abnormal sound.

1. The magnetic gap has debris. If debris enters the magnetic gap, the voice coil rubs against the debris when it vibrates, resulting in a hoarse voice.

2. Voice coil eraser. The position of the voice coil is not correct, and the magnetic core is rubbed and the sound is distorted. When repairing, the position of the voice coil should be corrected or the voice coil should be replaced.

3. The cone is broken. Damaged areas should be replaced with large paper cones, small areas of damage can be used slightly thinner paper cones or other tough paper repair.

4. Bad box. Bad seal of the cabinet or loose installation of the decorative net cover may cause cracks during playback. In addition, when the cabinet plate is too thin, it causes resonance and abnormal sound may occur.

 

About MAONO

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