The loudspeaker in loudspeaker is the most vulnerable and easily damaged part in professional sound system. In order to reduce the risk of loudspeaker damage, measures should be taken from the aspects of system design, operation and use, as well as the protection of loudspeaker itself.

 

 

 

 

 

1. Cautions for operation

 

 

 

When operating, special attention should be paid to the appropriate volume output of the power amplifier, especially to avoid loudspeaker damage caused by some strong shock signals. When switching on or off, plugging in or pulling out the power plug and the signal lines of each component, the volume of the mixer should be properly turned down; the leaping of the microphone on the ground and the strong feedback scream will threaten the loudspeaker and should be avoided as far as possible. The starting and closing of professional audio system should be in the correct order: when starting, the power supply of each front stage (including signal source, mixer and processor) should be connected first, and then the power amplifier power supply should be connected finally; when shutting down, the voice volume of the mixer should be turned off to the minimum, then the power discharge source should be cut off, and finally the power supply of each front stage should be turned off. In this way, the impact on the loudspeaker can be minimized. Now there is a power supply sequencer, using the action of electronic delay relay, so that each equipment can be connected and cut off according to the pre-set sequence, improving the safety of operation, avoiding unnecessary losses caused by misoperation of managers.

 

 

 

 

 

2. Avoid endangering loudspeakers due to clipping distortion

 

 

 

All the energy that burns down the speaker unit comes from the power amplifier. An amplifier with excessive rated output power will pose a threat to loudspeakers with low rated output power. Any professional audio system designer and operator should pay attention to and avoid this situation. But in many business halls, auditoriums and clubs of some units, people often encounter the trouble of a power amplifier with low power, which burns the loudspeaker unconsciously.

 

 

 

To find out why the small power amplifier burns the high-powered loudspeaker in the loudspeaker, two problems should be solved first: the characteristics of the music signal and the output power of the power amplifier.

 

 

 

 

 

3. Loudspeaker protection circuit

 

 

 

In order to solve the burnout problem of high-pitch loudspeakers, manufacturers have developed many new loudspeaker protection circuits, which can make products work safely at full load, such as JBL speakers.

 

 

 

Generally speaking, there are two schemes for loudspeaker protection circuit design. One is short circuit protection, which disconnects the signal before the loudspeaker unit is overloaded. This design protects the speaker, but interrupts the performance and affects the performance atmosphere. The other is a controller for high-end series products, which uses multiple sets of limiters to limit the amplitude of the signal. The chance of road overload is very small, but it will inhibit the dynamics of music and make the performance dull. The above two are compromise solutions. JBL audio manufacturer introduces that sonic guard can overcome the above problems. When the average power is too high, its protection system will bypass excessive energy, attenuate the destructive pulse to a safe level, and protect the speaker from burning.

 

 

 

JBL's tweeter protection circuit is also equipped with a conspicuous indicator, which shows the working status of the protection system with an indicator lamp, prompting the user to adjust the input power, so as to avoid burning other components besides the tweeter by long-term use of high-power input.