The horn type loudspeaker is composed of a loudspeaker and other parts. The excitation part is composed of magnet, voice coil and diaphragm. The excitation principle is the same as that of ordinary electric speakers. When the coil in the speaker is energized, its coil will generate a magnetic field. Under the interaction with the magnetic field of the magnet, the conductor coil will vibrate, and the vibration will make a sound, which is the force exerted by the energized conductor in the magnetic field. When the AC audio current passes through the loudspeaker coil (voice coil), the corresponding magnetic field will be generated in the voice coil. The magnetic field interacts with the magnetic field generated by the permanent magnet on the horn loudspeaker. Therefore, this force makes the voice coil vibrate in the magnetic field of the speaker's own permanent magnet with the audio current. The diaphragm of the speaker is connected to the voice coil, so the diaphragm also vibrates. The vibration produces the same sound as the original audio signal waveform.
The excitation part of PA loudspeaker is usually similar to spherical loudspeaker, and the diaphragm is also spherical (or inverted spherical); In order to obtain proper compliance, folding rings are also provided. In general, the horn made of resin and diaphragm is pressed together, which acts as an acoustic impedance converter. It is matched with the acoustic impedance of the exciter and the horn. The vibration of the acoustic film of the exciter is transmitted to the horn, pushing a large area of air to radiate sound waves into space.
The phase correction plug is used to adjust the distance from each point of the diaphragm to the throat of the horn, so that the acoustic wave excited by each point of the diaphragm reaches the throat with the same phase, so as to reduce the phase interference. The horn type loudspeaker has the advantages of strong directivity, high power and high efficiency, so it is widely used in venues, fields, gardens and other fields. The professional high-frequency loudspeaker has the characteristics of good sound quality and good frequency response, and is mainly used in theaters and other places with high requirements.