Click on the image to check the artwork
By certification 
The 20mm speaker unit is a circular, internally welded, thin speaker with a high frequency bandwidth of 20KHz. It use PCB contact and adopts the spring leading out methodand, which is convenient for the whole machine assembly. The 20mm speaker unit can be applied to the speaker of cordless phone, mobile phone for the elderly, recording pen, etc
The core component responsible for sound in audio equipment is the speaker unit, whether it is a speaker or a headset, this key component is indispensable. The speaker unit is a transducer device that converts electrical signals into acoustic signals. The performance of the speaker unit has a great influence on the sound quality, and the magnets in the speaker unit determine its performance to a large extent. In the case of the same magnet volume and the same voice coil, the magnet performance has a direct impact on the sound quality of the speaker.
The 20mm speaker unit uses NdFeB with the best performance, which is small in size, high in power and wide in frequency range under the same magnetic flux. At present, many headphones basically use this type of magnet.
Rated Input |
0.5W |
Max Input |
0.7W |
Freq.range |
550Hz |
Impedance at IKHz |
8±15%Ω |
SPL at 1KHz |
87.5±3dB 0.89V/ 0.1m |
We have person stay on the production lines do to the inspection. All products must have been inspected before delivery. We do inline inspection and final inspection.
1. All raw material checked once it arrive our factory.
2. All pieces and logo and all details checked during production.
3. All packing details checked during production.
4. All production quality and packing checked on final inspection after finished.
The speaker unit is one of the electro-acoustic materials. The basic material for making the speaker is the permanent magnet. The speaker magnet is generally called the horn magnet. NdFeB magnets and ferrite magnets are both good materials for making speakers.
How speakers work
The permanent magnet generates a magnetic field in the annular air gap of the magnetic circuit through the yoke, and the voice coil connected with the speaker cone is inserted into the annular air gap. The permanent magnets are surrounded by an external yoke iron, thus avoiding the interference of external stray magnetic fields. In turn, it can reduce the effects of the permanent magnet's magnetic field on the outside world. Coils are formed when sound passes through a magnetic field in the form of an electric current. Due to the change of current intensity, it will generate different vibration frequencies, and then drive the paper cone to emit different frequencies and strong sounds.
Magnets in speakers
The two most commonly used magnetic materials for speakers are NdFeB magnets and ferrites. Both are powerful, but have their own unique features.
The advantages of NdFeB are high cost performance and good mechanical properties, but the disadvantages are low Curie temperature, poor temperature characteristics, easy powdering and corrosion. Manufacturers of bass headphone speakers had to adjust their chemistry and use surface treatments to improve it. Only in this way can manufacturers of mid-range and high-range headphone speakers meet the requirements of practical applications.
NdFeB belongs to the third generation of rare earth permanent magnets. It has the characteristics of small size, light weight and strong magnetism. It is a magnet with good cost performance and is known as the king of magnets in the field of magnets. The advantages of high energy density make NdFeB permanent magnets widely used in modern industry and electronic technology. In the bare magnetic state, the magnetic force can reach about 3500 Gauss.
Ferrite is a ferromagnetic metal oxide. In terms of electrical properties, the resistivity of ferrite is much greater than that of metal and alloy magnetic materials, and it also has higher dielectric properties. The magnetism of ferrite also shows high permeability at high frequencies. Therefore, ferrite has become a non-metallic magnetic material widely used in the field of high frequency and weak current.
Ferrite is a non-metallic magnetic material. It is a composite oxide of magnetic ferric oxide and one or more other metal oxides. Magnetic force is usually 800-1000 Gauss. It is usually used for speakers and other musical instruments.
http://www.acousticunit.com/
