The difference between earpiece and speaker

earpiece

　　 The handset is an accessory used by communication tools such as telephones, walkie-talkies, and mobile phones to transmit sound. It is a type of speaker, but it is generally not called a speaker. Generally, this term is used to describe the parts of electronic products that transmit sound. Such as: mobile phones, walkie-talkies, etc.

Both the microphone and the earpiece will have a small membrane. The membrane in the microphone acts as the tympanic membrane of the human ear. When you speak to it, the membrane will vibrate, and the membrane will be connected to a small coil (Note: This coil will vibrate with the membrane. While changing the position), there is a small fixed permanent magnet in the microphone (fixed on the microphone housing). The membrane is elastic, and generally not only plays a role in vibration, but also plays a role in pulling the coil back to its original position. One end of the film is fixed on the microphone housing, and the other end is connected to the coil.

　　 When the film vibrates, the coil is driven to vibrate, and the relative position of the coil and the permanent magnet is changed, which changes the magnetic field passing through the coil. The change of the magnetic field will generate an induced electromotive force in the coil, which also generates a current. A specific sound has a specific vibration, and a specific vibration produces a specific form of electric current. So the microphone "encodes" the sound into the form of electric current.

The principle of the 　　 earpiece is probably the reverse process of the microphone, and the structure is almost the same. There is also a film in the earpiece, the film is connected to a coil, and there is also a permanent magnet. A specific form of current (such as the current that has just been "encoded" by the microphone) flows through the coil of the earpiece, so that the magnetic field generated by the coil changes, so the magnetic force between the permanent magnet and the coil changes, so the distance between the permanent magnet and the coil Will change. This drives the diaphragm to vibrate and make sound.

　　 speaker

　　 Speakers are also called "horns". It is a very commonly used electro-acoustic transducer device, which can be seen in sound-producing electronic and electrical equipment.

　　 composition structure

　　 Loudspeaker is a kind of transducer device that converts electric signal into acoustic signal. The performance of loudspeaker has a great influence on sound quality. The speaker is the weakest device in audio equipment, and it is the most important component for audio effects. There are many types of speakers, and the prices vary greatly. The audio electric energy makes the cone or diaphragm vibrate and resonate (resonate) with the surrounding air to produce sound through electromagnetic, piezoelectric or electrostatic effects.

Low-end plastic speakers have no sound quality at all because of their thin cabinets and inability to overcome resonance (some well-designed plastic speakers are far better than poor-quality wooden speakers); wooden speakers reduce the sound stain caused by cabinet resonance. The sound quality is generally better than that of plastic speakers.

　　Usually multimedia speakers are designed with two-unit two-way frequency. A smaller speaker is responsible for the output of mid-to-high range, and another larger speaker is responsible for the output of mid-bass.

The material of these two speakers should be considered when selecting speakers: The tweeter of multimedia active speakers is now mainly soft dome (in addition to the titanium dome used for analog sound sources, etc.), it can reduce high frequencies in conjunction with digital sound sources. The harshness of the signal gives a gentle, smooth, and delicate feeling. Multimedia speakers are now mostly made of soft dome tops such as better quality silk films and lower cost PV films.

　　 Woofer determines the characteristics of the sound of the speaker. It is relatively important to choose. The most common ones are the following: paper cones, paper cones, paper-based wool cones, compacted cones, etc. The paper cone has natural sound, cheap, good rigidity, lighter material and high sensitivity. The disadvantages are poor moisture resistance and difficult to control consistency during manufacturing. However, the paper cones made of top HiFi systems abound, because the sound output is very average. Good reducibility.

　　The difference between earpiece and speaker

　　Common speakers

　　 bulletproof cloth, with a wider frequency response and lower distortion, is the first choice for those who love strong bass. The disadvantages are high cost, complicated production process, low sensitivity and poor music effect.

　　Wool woven basin, the texture is soft, it is very good for soft music and light music, but the bass effect is not good, lack of strength and shock.

　　PP (polypropylene) basin, which is widely popular in high-end speakers, has good consistency and low distortion, and its performance in all aspects is remarkable. In addition, fiber diaphragms and composite material diaphragms are rarely used in popular speakers due to their high prices.

　　 The loudspeaker size is naturally the bigger the better, the large-diameter woofer can have better performance in the low frequency part, which can be selected in the purchase. Speakers made with high-performance speakers mean lower transient distortion and better sound quality. The speakers of ordinary multimedia speakers' woofers are mostly between 3 and 5 inches. Speakers made with high-performance speakers also mean lower transient distortion and better sound quality.

　　 Our most common electric cone speaker. Electric cone loudspeakers are often referred to as paper cone loudspeakers in the past. Although the diaphragm is still dominated by paper cones in 2014, many polymer material and metal diaphragms have appeared at the same time. The conical loudspeaker is called the name symbol. Actually. The cone loudspeaker is roughly composed of magnetic circuit system (permanent magnet, core column, magnetic conductive plate), vibration system (paper cone, voice coil) and support auxiliary system (centering support piece, cone frame, cushion edge), etc. Partial composition.

  1. Voice coil: The voice coil is the drive unit of the cone-shaped paper cone speaker. It is wound on the paper tube in two layers with very thin copper wires. Generally there are dozens of turns, also called coils, placed on the magnetic core column and In the magnetic gap formed by the magnetic conductive plate. The voice coil and the paper cone are fixed together. When the sound current signal passes through the voice coil, the vibration of the voice coil drives the paper cone to vibrate.

  2. Paper cone: There are many kinds of materials used in the cone diaphragm of the cone cone speaker. Generally, there are two types of natural fiber and man-made fiber. Natural fibers often use cotton, wood, wool, spun silk, etc., while man-made fibers use rayon, nylon, and glass fibers. Since the paper cone is the sound radiating device of the loudspeaker, it determines the sound reproduction performance of the loudspeaker to a large extent. Therefore, no matter which kind of paper cone, it is required to be light and rigid, and not deformed due to changes in ambient temperature and humidity. .

　　3. Folding ring: The folding ring is designed to ensure that the paper cone moves along the axial direction of the speaker and restrict the lateral movement. At the same time, it plays a role in blocking the air flow between the front and the back of the paper cone. In addition to the commonly used paper cone materials, the material of the folding ring also uses plastic, natural rubber, etc., to be bonded to the paper cone through hot pressing.

　　4. Centering support piece: The centering support piece is used to support the joint part of the voice coil and the paper cone to ensure that it is vertical and not skewed. There are many concentric rings on the centering support piece, so that the voice coil can move up and down freely in the magnetic gap without lateral movement, so as to ensure that the voice coil does not collide with the magnetic conductive plate. The dust cover on the centering support piece is to prevent external dust from falling into the magnetic gap, to avoid friction between dust and the voice coil, and abnormal sound from the speaker.