Structure and working principle of electronic alarm loudspeaker

2023 01/31

Electronic alarm loudspeakers are widely used, including paper basin type, speaker type and dome type. Only the first two are introduced here.

1. Paper basin horn speaker

Paper cone speakers are also called dynamic horn speakers.

It consists of three parts: ① vibration system, including conical paper basin, voice coil and centering support; (2) Magnetic circuit system, including permanent magnet, magnetic guide plate, excitation core column, etc. ③ Auxiliary system, including basin frame, wiring board, blank holder and dust cover, etc. When the audio current passes through the voice coil in the magnetic field, a magnetic field that changes with the audio current will be generated. This magnetic field interacts with the magnetic field of the permanent magnet to make the voice coil vibrate along the axial direction. But the speaker has simple structure, full bass, soft sound quality, wide frequency band, but low efficiency.

2. Horn loudspeaker

The horn type speaker structure is composed of two parts: vibration system (tweeter) and horn. The vibration system is similar to a paper basin speaker, but its diaphragm is not a paper basin, but a dome-shaped diaphragm. The vibration of the diaphragm radiates sound waves into the air through the horn (after two reflections). Because of its high frequency and high volume, it is often used for outdoor and square sound reinforcement.