Wednesday, December 29, 2010

Weak current College】 【speaker burning problem analysis.


First is the bass driver catches fire, in fact, the driver and the divider can fire because of their own quality very, very good. On this view, usually the owner will not be accepted. To this end, we specifically to examine the reasons, because the driver from the sound input to the voice coil itself after several road, electrical connections, the wound voice coil itself though is a line from beginning to end with no interface, but the entire voice coil line in the drawing process there is always a location may be in the Middle will produce some uneven. Therefore, typically current throughout the voice coil wire in different parts of the current density are strong or weak difference, voice coil with pin connection point will likely lead to poor contact between the contact resistance increase, all these factors result when added to the speaker's power continues too large, more than the rated power toleration speakers, this loudspeaker unit electrical loop a weak link in a crash occurs.

In other words, Horn, electric loop open burning, the speaker's bass section will stop working, no sound!, this is a normal situation, however, very occasionally, there will be a speaker, originally appear weak links in section does not appear, the entire electrical connections loop they are very strong (i.e. the quality of the speakers from head to tail do very well). When added to the speaker's power continues too large, more than the rated power toleration sound, it should be no blow blowing, however, have very high temperature voice coil, usually you can reach several hundred degrees Celsius, and now some voice coil skeleton material itself can withstand very high temperatures, no deformation of the voice coil (voice coil skeleton deformation will be met and the voice coil with magnetic circuit resulting in damage to the burnt voice coil).

This situation persists, the continuous high temperature voice coil pots drying with paper (paper trough bear several hundred degrees), this is the driver is on fire. If electrical loop can burn off road early, voice coil is hot, no opportunity to bake a cone, and treble unit-film is often not combustible, treble does not catch fire. Therefore, for the bass driver catches fire, we don't have a cow, you need to make patient explanation. But very strong overload may rapidly destroying the driver's voice coil and dividers, usually does not cause the fire because they may be too late to burning hot has burnt out, this is why our analysis on fire to note problems.

Alternatively, speaker internal fire is a divider hot ignite speakers inside other materials, but before the result is a driver (also includes treble unit loop) electrical connections open, have not been timely detection of, and continue to transfer the high-power signal; divider inside L/C (inductive/capacitive) crossover network is connected to the speaker load must be before forming the "filter" properties of the network, you can put the whole band audio signal according to the different audio segment is assigned to the corresponding driver, to distribute the signal of that once the driver open burning, electrical connections. In other words, there is no crossover network load, this time in the Horn of crossover network becomes an electrical "series on the notch network" circuit, amplifier output connections is an inductance and capacitance concatenated to form a network of notch in the audio signal to a frequency on very low impedance, approximate short circuit, but also not really short circuit, which may not be able to trigger the power amplifier circuit protection.

If the amplifier without overload protection actions, continuous rushed to the strong current divider will cause the inductance coil heating, if the inductance coil winding and enough crude (that is, its own quality very good), a short time is not blowing, then have the opportunity to take it around the ignition of the material. If inductive or capacitive fragile, the morning was a strong current completely destroyed, the divider is not heating ignition speakers. Only damaged power amplifier (for example, the output appears DC) while damaging the bass driver, but does not make the divider overheating on fire because the inductance capacitor network not by DC.

From the above analysis, to completely avoid speaker on fire, somewhat more difficult, although it is no accident. To avoid it to happen, we must strictly observe the following rules:

1. avoid system overload, speakers and the amplifier's power reserve must be adequate, it is absolutely fundamental to effective solutions, whether that situation of fire are caused because of overload.

2. regular checks sound system, ensuring that each speaker is normal. Very often, the speaker of a large number of damaged because no timely examination system caused when a speaker burn out, resulting in lower overall sound pressure, then by increasing the total volume to compensate for this and increase the burden of the other speakers, then damage, this vicious circle, speaker damage more and more, individual "quality"-good speakers might appear on fire.

3. avoid excessive volume, on-site sound sense of shock and not by simply increasing the volume will be able to do so, typically, sound pressure in 105 ~ 110 decibels is very adequate.
4. the speaker setup, avoid surrounding combustible materials, to avoid speaker fire ignited by the surrounding environment. Remind owners fully ready to fire safety work, after all, the industry is their own, this money can not be province.

In the speaker system work in case of ignition occurs. This often leads to consumer fears, but also to project developers a lot of trouble, in this case, the owner usually immediately finds the sound quality is too low. So, on this phenomenon have a correct understanding of the very necessary, it also helps prevent the fire from occurring.

Speaker on fire in General is the bass driver cone ignition and speaker internal fire, then further other parts ignition speaker on fire, two fire situation has the potential to cause other fire, we start to analyze the cause of the fire box.



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