Earphones and headphones are the most used gadgets nowadays, we often use them to listen to music, watch movies and take calls.
When it comes to buying the best earphone, everyone except the best sound quality in the earphones, but few of us know about the drivers that come inside the earphones, which provides better sound signature. The sound quality that we are expecting in earphones depends on the driver’s factor such as driver type, size, magnets and voice coil.
In this article we are discussing the driver’s speakers, its advantages and disadvantages. We hope this piece of information will help you pick the right earphone or headphone for you.
So without further ado, let’s dive right in.
What is the driver in speakers?
Before we dive right into the type of drivers, let’s first understand: what are speaker drivers? And what are the components used inside the drivers? We often heard the word “speakers”, but few of us hardly heard the term “speaker drivers”.
The drivers are the most important factor in the speakers that produce the sound by converting the electric audio signals into sound production.
The drivers come with different diameter sizes, and depending upon needs: such as earphones has small diameter drivers ranging from 7-15mm and for the headphones come with larger diameter compared to the earphones, it ranges from 30-50mm, and for the larger speakers, it goes on.
The larger the diameter of the speaker driver, the larger the audio output. Some earphones have multiple drivers for playing notes at different frequencies.
It usually builds the drivers with three major components, which together produce the sound from electrical audio singles.
These components comprise a magnet, Voice coil and the diaphragm.
Magnet: The magnet is the part of the driver who creates the magnetic field for producing the sound.
The sound quality of the speaker drivers depends on the magnets, which are used inside the drivers. Magnet performance can improve the sound quality of magnetic circuits.
The cobalt and ferrite, these two magnets mostly used for making Bluetooth earphones drivers. and also sometimes manufactures use rare material to reinforce magnets.
Voice coils: A voice coil is the copper wire winding that is attached to the apex of a loudspeaker cone. Whenever a current passes through a sound coil, the diaphragm moves and produces an audible sound.
The voice coils are converting electrical signals into sound, and it plays a vital role in the drivers. The copper wire is most commonly used material in the voice coil, but for better sound reproduction, the companies are applying an oxygen-free copper and Pure Copper By Ohno Continuous Casting.
The Diaphragm (cone): The diaphragm transducer designed to transform mechanical vibrations into sound waves.
For the construction of the diaphragm, most of the manufacturers are using the thin membrane or sheet of particular materials and suspended at its edges to produce the diaphragm.
When the diaphragm vibrates electrically, it hits the air and generates sound waves.
How does a speaker driver produce sound?
A diaphragm (cone) attached to the voice coil when the host device produces an electric current that passes through the “voice coil”. This creates a magnetic field around the coil.
Therefore, changes in the current flowing through the speaker are converted into a changing magnetic field, and the interaction with the driver’s magnetic field causes the speaker’s diaphragm to move.
This causes the driver to generate airwaves similar to the original signal from the host device.
Type of drivers
In the market, you will find 6 major drivers types inside the headphones/earphones.
- Dynamic Driver Unit
- Planar Magnetic Drivers
- Electrostatic Drivers
- Magnetostriction or Bone Conduction Drivers
- Balanced Armature Unit
- Hybrid Drivers
Dynamic Driver Unit
Dynamic Driver Unit is the most common driver type that is used in the headphones/earphones in the market.
These driver types are available in the market at comparatively low prices. The Dynamic Driver Unit has also called moving coil drivers because its voice coil and the diaphragm moves inside the drivers to produce sound. The Dynamic Driver Unit uses a physics of electromagnetism and magnetism for creating a movement to produce the sound waves.
A Dynamic Driver Unit comprises three major parts–a magnet, a voice coil, and a diaphragm.
Insides the Dynamic driver
The neodymium strip most popular magnet that is used in the earphones and headphone, neodymium is the best magnet which is one of the most powerful and rare magnets available on earth.
Headphone/earphone speaker drivers also come with ferrite magnets, which are not as efficient as neodymium magnets.
Coming to the Voice coil, which is inserted inside the drives that are made from conducting materials such as copper.
The diaphragm is a cone-shaped paper that is attached with a voice coil, and it covers the speaker’s internal hardware.
How Dynamic driver work?
When the electrical signals pass through the voice coil inside the drivers, it makes the voice coil turn into an electromagnet.
The magnetic field causes the voice coil and diaphragm to move back and forth rapidly, pushing away the surrounding air and making a sound.
- Dynamic Drivers are very affordable
- Excellent bass response
- Not require much power to produce a loud sound
- Drivers can’t deliver very detailed sound
- Prone to high-volume distortion.
Planar Magnetic Drivers
Planner Magnetic Drivers are like the dynamic driver units, which rely upon the principle of electromagnetism.
You will find this Planner Magnetic Drivers in high-end headphones and these drivers are used for expensive premium Bluetooth earphones as compared to the dynamic drivers.
Inside the Planar magnetic Driver
Image source: bhphotovideo.com
How planar magnetic Drivers work?
The voice coils inside the planar magnetic drivers pass around the diaphragm with a static magnet in the vicinity. When the electric single run through the voice coil, the diaphragm itself moves back and forth, making the sound waves.
- Excellent bass response
- Minimal sound distortion
- precise sound production
- Considerably heavier than standard designs
Electrostatic drivers are the most expensive and more complicated drivers in the market and are used for specific use-cases. In Electrostatic drivers use the very thin diaphragm which is placed between the two metal plates.
Image source: Wikipedia
How Electrostatic drivers work?
Electrostatic drivers are to take an advantage of static electricity to produce an electric field. These electric fields create oscillations, which move the diaphragm back and forth against the conductive plates (electrodes). This action and continuously changing electrical signals create sound waves that the ear perceives.
- Produces better sound than all other drivers
- Zero distortion sound output
- Wide frequency response range
- Very expensive
Magnetostriction or Bone Conduction Drivers
Bone conduction drivers are a unique and relatively new technology that doesn’t work like other earphone drivers. Bone Conduction Drivers also called Magnetostriction drivers.
There is no need to wear such earpieces inside your ear canal, but still, these types of earphones transfer audio singles through the bone to the inner ear of the skull.
Image source: panasonic.net
How does a Magnetostriction or Bone Conduction driver work?
The Magnetostriction or Bone Conduction Drivers comes with a vibration driver (as above shown). This vibration driver or transducer transfers the audio signals into physical vibration signals, which pass those signals through our face bones to our inner ear.
You will find two types of bone conduction drivers in the market, which are magnetostriction and mechanical. Both drivers work on the same principles.
- Very helpful for those who lost eardrums.
- You can listen to external sounds while enjoying music
- Does not deliver effective sound as compare to others driver
- Very Expensive
Balanced Armature Unit
Balanced Armature unit drivers are much smaller and expensive drivers as compared to the dynamic drivers, and these drivers are only available in In-ear Monitor (IEM).
How does Balanced Armature work?
Balanced Armature driver Inside
Balanced armature driver comprises Permanent magnet, Balanced armature, coil, Pivot and Diaphragm.
Inside the driver, the armature has wrapped with a coil which is placed between two magnets. The movement of the armature depends on the top and bottom magnets, the armature itself being correctly balanced between these two magnets when the electric signal or current does not pass through the coil.
On other hand, you can see that the armature has a joint with the centre of the diaphragm. When an electric current passes through the coil, it makes the armature magnetize, which forces the armature to move to oscillate back-and-forth to generate sound waves.
- Small size
- More efficient than Dynamic driver
- Excellent treble response
- Clean and crisp high-frequency sound output
- More expensive than dynamic drivers
- For better response requires additional drivers
The Hybrid drivers comprise multiple drivers type of, such as Dynamic driver and balanced armature driver, with the combination of these drivers, earphones deliver pleasant sound output. The dynamic driver generates lower-middle and lower frequencies. While balanced armament provides mid, high mids, and high frequencies.
The manufacturers are using these types of earphone drivers to offer the audiophiles demand in the market, The sound output you will get from this driver will be vibrant, wide and responsive bass.
- high-frequency sound output
- increase bass response and frequency clarity
- This driver is rarely available on wireless headphones.