When people go out now, in addition to mobile phones, earphones may be the most frequently carried device. People on the subway are all wearing earphones and playing mobile phones.
Most of the earphones we can see are dynamic earphones. In addition, moving iron earphones are another relatively expensive earphone. These two are the two mainstream earphones on the market today. Maybe classmates who often listen to songs have heard of their names before, but they may not know them well. So, what are the commonalities and differences between them?
Also known as electric headset. At present, most affordable ear canal earphones fall into this category. The principle is similar to that of a dynamic speaker. A cylindrical coil wound in a permanent magnetic field is connected to the diaphragm, and the coil drives the diaphragm to sound under the signal current.
Generally speaking, the volume of moving coil earphones is relatively large, because under the limitation of the current technical level, the moving coil unit as shown in the figure above must have a certain size. There is a formula in physics: P=Fv. P is power, F is force, and v is speed. When doing low-frequency vibration, the speed of the coil and the diaphragm is very small, so when the power P is constant, the driving force F has to be increased, and the size of the driving force is proportional to the cross-sectional area of the magnetic field. Therefore, if the structure of the moving coil unit is too small, the force generated when the current passes is not enough to make the coil drive the diaphragm to do some low-frequency vibration, and the bass performance of the headset will be greatly reduced. However, there are still many dynamic earphones that are small in size but have good sound quality, and they are only in general terms relative to dynamic iron earphones.
The current manufacturing process of dynamic earphones is very mature, so the manufacturing cost is much lower than that of dynamic iron earphones, which is one of the reasons why it is widely used. Searching for headphones on a treasure, most of the few to dozens of dollars that come into view are dynamic headphones. These headphones seem to be really cheap, but their cost is really low. Many of them may be only one or two yuan or even a few dimes. The biggest common problem of these headphones should be the serious lack of low-frequency presentation. After wearing them, you may not hear the bass part of the music at all. (It seems to have found a reason why the bassist was hacked and ignored.)
A dynamic earphone that reaches the qualified line has a natural sense of hearing and a warmer sound. In addition, the sound field of dynamic earphones is relatively large, which is also its biggest advantage over dynamic iron earphones. The disadvantage may still be the problem of bass. It may be uncomfortable to listen to music styles such as rock, jazz, etc. that emphasize bass with relatively cheap dynamic headphones. Of course, except for the local tyrants who use unusual dynamic headphones.
Moving iron headset
Moving iron earphones are also called balanced armature earphones. It uses an electromagnet to generate an alternating magnetic field, and its vibrating part is an iron piece suspended in front of the electromagnet. When the signal passes through the electromagnet, the magnetic field of the electromagnet will change, so that the iron sheet drives the diaphragm to vibrate and produce sound. The advantages of moving iron earphones are low distortion, high sensitivity, and small size. The disadvantage is high cost, and they are often used in high-end earphones. More advanced moving iron earplugs use double-balanced armature drivers to bring studio-like sound.
The moving iron unit in the moving iron earphone is naturally the core of the moving iron earphone. The moving iron unit is basically constructed by placing a magnet on one end of a U-shaped iron sheet and winding a coil on the other end. After being energized, one end of the U-shaped iron sheet is affected by the current and magnetic field and vibrates, driving the diaphragm plate connected to it to vibrate and sound.
Moving iron earphones are far better than moving coil earphones in terms of music dynamics, instant detail performance, and sound density. In contrast, the price of moving iron earphones is not so close to the people. An entry-level moving iron earphone may cost a few hundred yuan. It cannot compete with moving earphones among mass consumers. Many people have never heard of it. One of the reasons for overmoving iron earphones, after all, moving iron units were generally only used in more sophisticated instruments such as hearing aids. In addition, the moving iron unit can be made smaller due to the structure, so there is a multi-unit moving iron earphone. These headphones are particularly good at presenting the overall frequency of the sound.
Of course, moving iron headphones are not without their shortcomings. Compared with the starter ring headset, its disadvantage lies in the sound field. Moreover, although its frequency rendering ability is relatively strong, the low frequency rendering is not as natural as dynamic headphones.
With the development of technology, coil-iron earphones that combine the advantages of the moving-coil unit and the moving-iron unit have now appeared. This kind of earphone allows the moving coil unit and the moving iron unit to be responsible for the frequencies they are good at, so that the overall sound presentation effect has been greatly improved. I believe that in the near future, we can hear a more perfect sound in the headset.