An announcement speaker is a transducer that transforms electrical signals into acoustic signals. The performance of speakers has great influence on their sound quality. The speaker is the weakest device in the sound equipment, but for the sound effect, it is the most important component. There are many kinds of speakers and the price varies widely. The audio power can make the paper basin or diaphragm vibrate and resonate with the surrounding air through the electromagnetic, piezoelectric or electrostatic effects and make a sound.
Usually an announcement speaker system is a dual unit frequency-interleaved design, a smaller loudspeaker is responsible for the output of the middle and high voice, while the other larger speaker is responsible for the output of the middle bass. The selection of the sound box should consider the material of the two speakers: the high sound unit of the multimedia active sound box is mainly using the softball top (besides there is also the titanium film ball top for the analog sound source). It can reduce the stiffness of the high frequency signal coordinated with the digital sound source, and give the feeling of gentle, smooth and delicate. Multimedia speakers are mostly made of silk film with better quality and PV film with lower cost. The bass unit determines the sound characteristics of the speakers, and it is more important to select them.
The size of the speaker is naturally bigger and better. The large diameter bass speaker can perform better in the low frequency part, which can be selected in the purchase. Sound box made of high-performance speakers implies lower transient distortion and better sound quality. The loudspeakers of ordinary multimedia speakers are mostly 3~5 inches.