What Makes Your Headphone Sound –Introduction of the Main Drivers Used On Headphones
by Bear Chen
by Bear Chen
Have you ever wondered how we hear the sound coming from the headphones? What mainly makes our headphones sound is the drivers used inside the headphones. They form a sound by receiving a signal, then transferring it into sound by some kind of sounding method.
There are mainly 4 kinds of drivers that is used on headphones, they are the Dynamic Driver, Balanced Armature Driver, Planar Magnetic Driver, and the Electrostatic Driver. Different drivers have different sounding methods, it also provides different kinds of sound.
Dynamic Driver is currently the most used drivers. Dynamic Drivers has the same sounding method as the speaker. There is a coil attached to the diaphragm of the Dynamic Driver, variational current passes through the coil to generate a magnetic field, which interacts with the permanent magnet below to cause the diaphragm to vibrate and produce sound. The coil and the material, diameter of the diaphragm has different factors, it does make a slight difference to the sound when the factors change.
Pros: It has a very natural sound and very comfortable bass
Cons: The drivers are quite big and it needs a lot of power to drive.
Balanced Armature Driver (BA Driver for short) have a very simple structure, it is another innovative evolution of the dynamic driver. Its coil is wound on a balanced armature located in the center of the permanent magnetic field, variational current magnetizes the armature, and the magnetic field generated by the permanent magnet acts on the magnetically changing armature, resulting in vibration. The vibrating armature conducts the vibration to the center point of the MSI diaphragm through the connecting rod, which drives the diaphragm to vibrate and produce sound.
Balanced Armature Drivers are firstly used on hearing aid. It can avoid the interference of external sound to the greatest extent, as it lies deep into the ear canal. With the development of the IEMs, multiple BA drivers are used to form different frequencies, as it can form a great transient and resolution.
Pros: The unit is particularly small, commonly used on IEMs, it’s super easy to drive and it forms great transient and resolution.
Cons: The sound is unnatural, some IEMs with BA drivers have too harsh tremble or lack of bass.
As to the Planar Magnetic Driver, it embed the coil n a thin diaphragm, and the permanent magnet is concentrated on one or both sides of the diaphragm, and the current changing in the coil in the diaphragm generates a magnetic field, which is subjected to force in the magnetic field generated by the permanent magnet, thereby vibrating and sounding
Planar magnetic headphones have high requirements for process accuracy, the most representative for planar magnetic headphones is the HIFIMAN and the Audeze. The UM uses Planar Magnetic Drivers on their IEM’s and it seems to be at the forefront of the IEM industry.
Pros: Planar Magnetic Drivers have advantages on the dynamic and the details of the sound.
Cons: Large heavy drivers, also requires much more power to drive, and the pricing is quite high compared to other driver headphones.
The Electrostatic Driver, which is used on the Sennheiser Orpheus, can be regarded as a major breakthrough in the sound unit, although its architecture still does not depart from the traditional sound principle architecture, but its unique sound principle can obtain a more realistic sound restoration. The method is that the audio model is amplified and connected to a fixed plate, and the changing audio signal will create a changing electric field between the two plates. The metal diaphragm of the headphone is between the two plates, and the extremely high voltage is connected to the diaphragm, and the diaphragm is subjected to the electric field of change in the audio signal, and the charge on the diaphragm is stressed, so that the diaphragm swings to form a sound.
Pros: Low distortion, large details, fast response, and wide frequency. a
Cons: It relies on the recording quality, and it requires a special amplifier.