The horn is burned out personnel is a headache problem we sound maintenance, either in place or KTV, and the bar scene. In order to allow the majority of peer friends to avoid the horn we burned, especially as we summed up eight reasons of some common horn burn, hope to help you after work.
1 speakers and power amplifier configuration is not reasonable
Many play the sound will think, the power amplifier output power is too large, is caused by the damage to the high unit. In fact, is not, in the professional situation, the speaker can generally withstand 2 times the rated power of the big signal shock, the instantaneous can withstand 4 times the rated power of the peak impact without problems.
So, not because of unexpected strong shock or microphone long time whistle, and the power amplifier power and burn the tweeter is an extremely rare occurrence. But if the power output of the power amplifier is too large, both the high and the bass units are likely to be damaged. If the power amplifier's power is insufficient, the signal overload appears clipping, the high order harmonic component will increase sharply. The signal was sine wave, square wave clipping close in overload, odd harmonics generated a large number of the high frequency components in the signal ratio increases greatly, resulting in high frequency power energy signal in far more than treble unit can bear.
Even when the total power of the signal has not yet reached the rated power of the speaker, but the high unit has been overloaded and cause damage. This kind of circumstance is short of signal overload, but does not appear to be more dangerous. In the signal without distortion, signal short-time overload, power energy falls in the bass unit larger power, maximum power not more than short-term speakers, generally will not cause the deviation of power allocation and damage the speaker speaker unit. Therefore, under normal operating conditions, the power amplifier rated output power should be 2 - 1 times the rated power of the speaker, to ensure that the maximum power amplifier in the speaker does not cause distortion.
2 improper use of frequency
External frequency division point of the use of the input point is not used properly, or the frequency range of the speaker is not reasonable in the high frequency unit is a cause of damage. In the use of frequency divider, it should be strictly according to the frequency range of the speaker provided by the manufacturers to select a reasonable frequency point. High pitched speakers of the frequency point if the choice is low, the burden is too heavy, it is easy to burn the high.
3 equalizer debugging
The adjustment of the equalizer is also crucial. Frequency equalizer is designed to compensate for the various defects of the indoor sound field and the speaker's frequency is not uniform, it should be used with the actual spectrum analyzer or other instruments to debug.
The transmission frequency characteristic after debugging should be relatively flat in a certain range. Many do not have the sound knowledge of the tuner to debug, and even a considerable number of people, the high frequency and low frequency of the equalizer is too high, the formation of the "V".
If the frequency and frequency is higher than 10dB compared to enhance the tenor (adjust the amount of equalizer in 12dB generally) words, not only caused the serious phase distortion equalizer to the sound of music at the same time, was also extremely easy to cause the sound tweeter burned, this kind of situation is the main reason for damage of the loudspeaker.
4 Volume Control
Many users to post amp the attenuator in -6dB, -10dB, 80% - 70% volume knob, even the general position, increase the input to the appropriate volume, that the power amplifier of a room, the speaker is safe, actually this is wrong. The power amplifier is the input signal attenuation attenuation knob, if the power amplifier input attenuation of 6dB, which means to maintain the same volume before must output 6dB voltage to 1 times higher on the dynamic margin input, will be cut in half.
At this time, if there is a burst of large signal, it will be early 6dB to make the output overload, the emergence of clipping waveform. Although the power amplifier is not overloaded, but the input is clipping and waveform, the treble component is overweight, not only high distortion, treble unit may also burn.
5 low cut choice caused by damage to the bass unit
Many tuners are not too low cut problem, in fact, this is caused by low shear damage maximum woofer bass horn and many risks, not very good to restore some ultra low frequency, such as frequencies below 40 Hz, but can not be reduced to the acoustic frequency components still exist, he converted to energy, our horn is composed of many parts with glue together, when long time high power input to horn component signal conversion rate not ultra low frequency, due to the volume of the box body space is limited, heat is not timely, a lot of heat accumulation, but can not afford a glue will melt, causing the elastic wave off, voice coil loose circle horn, damage.
The use of low cut, can greatly reduce the damage to the low frequency of the bass speaker. 6 different power amplifier at the same time the use of the input sensitivity of the difference
In the project, often have such a situation, is a different brand, mixed type power amplifier, there is an easily overlooked problem, the problem is the sensitivity of the input, this problem is often overlooked, is the same power amplifier, different types of possible sensitivity voltage is not uniform, such as two power amplifier, output power is 300 watts, A power amplifier input sensitivity is 0.775V, B power amplifier input sensitivity is 1.0V, so if the two power amplifier while receiving the same signal, when the signal voltage reaches 0.775V, A power output reached 300W, but the output B power amplifier only reached 150W, continue to improve the signal level. When the signal strength reaches 1.0V, A power amplifier overload, B power amplifier output power rated just reached 300W.
In such a case, the sound box unit which is connected with the overload signal is bound to be damaged. The same power amplifier with different sensitivity voltage when the input level to high sensitivity attenuation amplifier. It can be unified by adjusting the output level of the previous stage equipment or reducing the sensitivity of the power amplifier with high sensitivity. For example, the above said two Taiwan are 300W power output of the power amplifier, a voltage sensitivity is 1.0V, one is 0.775V, this time the input to the 0.775V amplifier level decreases 3 dB or the PA level on the two amplifier into position, at this time in the same time the input signal, the output power is the same.
7 big signal instantaneous disconnection causes the bass unit to die
In KTV, many times the box guests or DJ will have a very bad habit, that is, in the state of loud pressure to cut the song or mute. Especially when playing the music, it is easy to cause the sound of the bass unit ring ring or burned.
The audio signal input to the speaker through current, speakers by electromagnetic force driving cone done before and after exercise to make the air vibration become sound in large amplitude motion, suddenly cut off signal input, can easily lead to extreme sports after lost the ability to recover lead unit damage.
8 front stage, the components of the power amplifier
The circuit level output part of the resulting output sine wave frequency tone breakdown, similar to some frequency howling, and the output power is large, can lead directly to the bass unit because the power overload coil burning. Power amplifier due to the current breakdown into a DC output, so that the sound box is damaged.
Eight points summarized above are not only for the KTV site, but also for the bar and site, dear friends, you will burn out the past contrast horn with more than eight kinds of possibilities, there is no reason you burn the horn in the above eight points. |