There are many types of speakers. According to their energy conversion principles, they can be divided into electric type (i.e. moving coil type), electrostatic type (i.e. capacitive type), electromagnetic type (i.e. reed type), piezoelectric type (i.e. crystal type), etc. , the latter two are mostly used in rural cable broadcast networks; according to the frequency range, they can be divided into low-frequency speakers, mid-frequency speakers, and high-frequency speakers. These are often used as combination speakers in speakers.
According to the energy conversion mechanism and structure, it is divided into moving coil type (electric type), capacitive type (electrostatic type), piezoelectric type (crystal or ceramic), electromagnetic type (compression spring type), ion type and pneumatic type speakers, etc. Electric type Speakers have the advantages of good electroacoustic performance, solid structure, low cost, etc., and are widely used;
According to the sound radiation material, it is divided into paper cone type, horn type and diaphragm type; according to the shape of the paper cone, it is divided into round, oval, double paper cone and rubber ring; according to the working frequency, it is divided into bass, midrange and treble, and some are also divided into Special for recorders, special for TVs, ordinary and high-fidelity speakers, etc.; divided into low impedance and high impedance according to voice coil impedance; divided into direct radiation and ambient sound according to effect.
Speakers are divided into built-in speakers and external speakers, and external speakers are generally referred to as speakers. Built-in speakers mean that the MP4 player has a built-in speaker, so that the user can listen to the sound from the MP4 player not only through the headphone jack but also through the built-in speaker. MP4 players with built-in speakers eliminate the need for external speakers and avoid the inconvenience of wearing headphones for long periods of time.
