The loudspeaker is also called "horn". It is a very commonly used electro-acoustic transducer device, which can be seen in sound-emitting electronic and electrical equipment.
Speaker Profile
The loudspeaker is a transducer device that converts electrical signals into acoustic signals, and the performance of the loudspeaker has a great influence on the sound quality. The loudspeaker is the weakest part in the audio equipment, but it is the most important part for the sound effect. There are many types of speakers, and their prices vary widely. Audio electrical energy, through electromagnetic, piezoelectric or electrostatic effects, causes its cone or diaphragm to vibrate and resonate (resonate) with the surrounding air to produce sound.
The woofer determines the sound characteristics of the speaker, and it is relatively important to choose. The most common types are the following: paper cones, glued paper cones, paper-based wool cones, and pressed cones. The sound of paper cones is natural, cheap, good rigidity, light material and high sensitivity. The disadvantage is poor moisture resistance and difficult to control the consistency of manufacture. However, paper cones can be found everywhere in the top HiFi system, because the sound output is very average. Good reducibility.
Bulletproof cloth has a wider frequency response and lower distortion. It is the first choice for those who love strong bass. The disadvantages are high cost, complicated production process, low sensitivity, and poor light music effect.
Wool woven basin, soft texture, it performs very well for soft music and light music, but the bass effect is not good, lacking power 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 diaphragms are rarely used in popular speakers due to their high prices.
Our most common powered cone speaker. Electric cone speakers used to be referred to as paper cone speakers. Although paper cones were still the main diaphragm in 2014, many polymer material diaphragms and metal diaphragms appeared at the same time. Cone speakers are called cone speakers. Actually. The cone-shaped paper cone speaker is generally composed of three major components: the magnetic circuit system (permanent magnet, core column, magnetic plate), the vibration system (paper cone, voice coil) and the supporting auxiliary system (centering piece, basin frame, edge pad). 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 known as coils, placed between the magnetic core and the In the magnetic gap formed by the magnetic 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 for the cone diaphragm of the cone cone speaker, generally there are two categories: natural fiber and man-made fiber. Natural fibers often use cotton, wood, wool, spun silk, etc., while artificial fibers use rayon, nylon, glass fibers, etc. Since the paper cone is the sound radiation device of the speaker, it determines the sound reproduction performance of the speaker to a considerable extent, so no matter what kind of paper cone, it is required to be light in weight and good in rigidity, and cannot be deformed due to changes in ambient temperature and humidity. .
3. Surrounding ring: The folding ring is set to ensure the axial movement of the paper cone along the speaker and limit the lateral movement, and at the same time, it plays a role in blocking the circulation of the space between the front and rear of the paper cone. The material of the ring is not only the material of the commonly used paper cone, but also plastic, natural rubber, etc., which are bonded to the paper cone by 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 strut, so that the voice coil can move up and down freely in the magnetic gap without moving laterally, so as to ensure that the voice coil does not collide with the magnetic plate. The dust cover on the centering strut is to prevent the external dust from falling into the magnetic gap, avoiding the friction between the dust and the voice coil, which will cause the speaker to produce abnormal sound.
Basic Features of Speakers
(1) The speaker has two binding posts (two lead wires). When a single speaker is used, the two pins have no distinction between positive and negative polarity. When multiple speakers are used at the same time, the two pins have polarity.
(2) The speaker has a paper cone, which is usually black or white.
(3) The shape of the speaker has several categories such as round, square and oval.
(4) There is a magnet on the back of the speaker paper cone. When you use a metal screwdriver to touch the magnet with an external magnetic speaker, you will feel the presence of magnetism; there is no such feeling in the internal magnetic speaker, but there is a magnet inside the shell.
(5) The speaker is installed on the panel of the machine or inside the speaker.
Main types of speakers
There are many kinds of loudspeakers, which can be divided into electric type (that is, moving coil type), electrostatic type (that is, capacitive type), electromagnetic type (that is, reed type), piezoelectric type (that is, crystal type) and so on. , the latter two are mostly used in rural cable broadcasting networks; according to the frequency range, they can be divided into low-frequency speakers, intermediate-frequency speakers, and high-frequency speakers, which are often used as combined 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 (compressed spring type), ion type and pneumatic speaker, etc., electric type The loudspeaker has the advantages of good electro-acoustic performance, firm structure, low cost, etc., and is 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 circular, 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 tape recorder, special for TV, ordinary and high-fidelity speakers, etc.; according to voice coil impedance, it can be divided into low impedance and high impedance; according to effect, it can be divided into direct radiation and ambient sound, etc.
Speakers are divided into built-in speakers and external speakers, and external speakers are generally referred to as speakers. The built-in speaker means 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. The MP4 player with the built-in loudspeaker does not need an external sound box, and also avoids the inconvenience caused by wearing earphones for a long time.