The speaker system is one of the important components of audio equipment, usually composed of speakers, dividers, enclosures, sound-absorbing materials, etc. The failure rate of speaker systems is relatively low, with fewer types of faults. There are four common types of faults: silent, intermittent sound, low volume, and abnormal sound.

　　Silent fault reason:

1. The speaker wiring is broken or the frequency divider is abnormal. After the wiring of the speaker is broken, if there is no excitation voltage for the speaker unit, it will cause a silent fault. Frequency dividers are generally not prone to wire breakage, but faults such as lead joint desoldering and short circuit of frequency divider capacitors may occur.

2. The voice coil is broken. Use a multimeter R × 1 to measure the solder joint of the speaker lead wire. If the resistance value is ∞, use a small knife to scrape open the sealing paint of the leads at both ends of the voice coil, expose the bare copper wire, and then measure again. If it still does not work, it indicates that the voice coil is broken internally; If the measurement is connected and there is a 'click' sound, it indicates that the voice coil lead is broken. You can solder the wire end and then use another piece of enameled wire similar to the voice coil winding to solder it properly.

3. The speaker lead is broken. Due to frequent vibration of the speaker paper tray, the braided wire is prone to breakage, and sometimes the wire is broken, but the cotton core wire still remains connected. This type of braided wire is not easily available and can be replaced with slightly longer flexible wires.

4. The voice coil is burnt out. Measure the speaker lead wire with a multimeter R × 1. If the resistance value is close to 0 Ω and there is no 'click' sound, it indicates that the voice coil is burnt out. Before replacing the voice coil, the debris in the magnetic gap should be removed first, and then the new voice coil should be carefully placed in the magnetic gap. The voice coil should be straightened, and the upper and lower positions of the voice coil should be fixed with strong glue while listening. After the voice coil is placed in the optimal position, the gap between the voice coil and the paper tray should be filled to about half with strong glue. Finally, the dust cover should be sealed, and the speaker paper tray should be raised. After one day, it can be used normally.

　　Sometimes when the sound is heard * Reason:

1. Poor speaker wiring. It is usually caused by mold breakage or poor welding of the voice coil lead. When the paper tray vibrates frequently, the break point is sometimes connected and sometimes disconnected, forming an irregular intermittent noise fault.

2. The voice coil lead wire is broken or about to short circuit.

3. Poor contact of power amplifier output socket or broken input line of speaker.

　　low volumeCause of failure:

1. Poor performance of the speaker and decreased magnetic properties of the magnet. The sensitivity of a speaker mainly depends on the magnetism of the Yong Jiu magnet, the quality of the paper tray, and the quality of the assembly process. You can use ferromagnetic objects to touch the magnetic steel, and roughly estimate the strength of the magnetic steel's magnetism based on the magnitude of the attraction. If the magnetism is too weak, you can only replace the speaker.

2. The magnetic core column is loose. When the magnetic core column of the speaker becomes loose, it will be attracted to one side by the magnetic plate, causing the voice coil to be compressed and hindering normal sound production. During maintenance, you can lightly press the paper tray with your hand. If it cannot be moved, it may be due to the voice coil being pressed by the core column, and it needs to be disassembled and re glued before it can be used again.

3. The frequency divider is abnormal. When there is a faulty component in the frequency divider, the signal in the corresponding frequency band is blocked, and the speaker in that frequency band experiences a low volume fault. The focus should be on checking whether the frequency divider capacitor connected in parallel with the subwoofer is short circuited, and whether the frequency divider inductor coil connected in parallel with the tweeter is short circuited between layers.

　　Abnormal soundCause of failure:

1. There are impurities in the magnetic gap. If debris enters the magnetic gap, the voice coil will rub against the debris during vibration, resulting in hoarse sound.

2. Voice coil core cleaning. The position of the voice coil is not correct, causing friction with the magnetic core and resulting in sound distortion. During maintenance, the voice coil position should be corrected or replaced.

3. The paper tray is broken. For larger damaged areas, the paper tray should be replaced. For smaller damaged areas, a slightly thinner paper tray or other paper with better toughness can be used for repair.

4. Poor casing. Poor sealing of the box or inadequate installation of the decorative mesh cover can cause cracking sounds during playback. In addition, the thin board of the box can cause resonance and produce abnormal sound.