1,380-word post, approx. 3-4 min. read
This is part 4 in a series on Headphones and Their Drivers. Don’t hesitate to share and comment if you found these helpful!
- What is Headphone Impedance?
- What is Sensitivity in Headphones?
- What is Output Impedance?
- What is a Headphone Driver? (You are here)
- What is a Planar Magnetic Driver?
Hi friend and Welcome!
What is a headphone driver? Glad you asked! This is going to be a semi-condensed post on a forgotten topic that is a little glossed over in the mainstream headphone world.
Before we get started though, grab a snack, sit back, and relax because…
You’ve come to the right place!!
What is a Headphone driver?
What I will bring you in this review
- Introduction
- What is a headphone driver?
- Types of drivers
- Angled drivers
- Examples
- Final Word
Now without further ado, let’s get rolling!
Introduction
When I was first getting into the world of headphones, I never knew high-end models existed.
I basically assumed that the stuff I saw in stores was it.
That may sound completely ridiculous now, but back then the internet wasn’t as prominent as it is today.
I didn’t really have the luxury of typing a phrase into a box and instantly seeing a result.
Therefore, I actually considered those CVS models about as good as it got.
The more research I do, the more I realize that there is an almost endless amount of gear out there.
Some brand names I can’t even pronounce, and others sound as flamboyant as a 3 ring circus. Lol.
Ever heard of a headphone amplifier called the Eddie Current Balancing Act? I rest my case.
Going even further, all headphones have drivers, and some of these high-end model headphones have what are called angled drivers.
Huh? What’s a driver anyway?
What is a headphone driver?
The drivers inside of your headphones are responsible for converting the electrical signal into the sound that you hear, by creating a current with a conductor, through a magnetic field that moves a diaphragm, thus creating sound.
- Check out How Headphone Dynamic Drivers Work!
Think of them like tiny loudspeakers inside of the earcups. A driver unit is comprised of:
- A permanent magnet. Creates a magnetic field. The magnets are made from rare-earth ceramic materials—most commonly samarium-cobalt and neodymium-iron-boron.
- Voice coils. Responsible for moving the diaphragm that creates the sound you hear, by providing a linear motion back and forth when driven by an electrical audio signal. Since they are made of copper, they cannot create a charge by themselves. This is where the current comes in.
- A diaphragm. Moves back and forth, creating sound waves.
In a nutshell:
The magnetic field created by the permanent magnet interacts with the magnetic field created by the voice coil.
This creates the movement of the voice coil up and down, which in turn moves the diaphragm linearly, creating sound waves.
It is important to note:
The diameter of the diaphragm is usually stated in the specifications of the headphone and determines the overall quality of the sound.
The driver’s size is typically an indicator of how big the sound is.
A bigger driver unit will often times deliver the bass you’re looking for.
To put it simply: The bigger the unit, the larger the speaker and the more powerful the output is.
Driver sizes for earbuds
- 8mm to 15 mm
Driver sizes for headphones
- 20mm to 50mm
Types of drivers
Planar Magnetic Driver.
There are a few to speak of:
Dynamic drivers
These are the most common and use larger diaphragms.
They do a better job at giving you a powerful bass, achieving good sound pressure with less power.
This is the type you will find most common in consumer-grade headphones, but bigger sound doesn’t always equal better. It means there is more of it.
Balanced Armature drivers
These are found mostly with in-ear monitors and are very small.
Most in-ear monitors have between 1-4 of these, but custom IEMs can have up to 20!
Planar Magnetic Drivers.
Found in higher-end headphones, and the diaphragm rests between the magnets.
These can be found in a lot of audiophile-grade headphones such as the Audeze LCD-3.
- Find out How planar magnetic headphones work!
Electrostatic drivers
Very expensive and somewhat uncommon.
They use a thin electrically-charged diaphragm that’s placed between two conductive plates or electrodes.
A special amp is needed to boost the sound to a listenable level.
A Dynamic Driver | Image: Earphone DIY Labs
In a nutshell:
- Planar magnetic headphones use a magnetic field around a conductor.
- This conductor has an electrical current flowing through it.
- That electrical current drives the diaphragm.
- Magnets are placed in front of and behind the diaphragm evenly.
- As current passes through the conductors, the magnetic field created by current flow interacts with the field created by the magnets.
- This causes the conductors and the diaphragm to move.
- This produces the sound you hear, and in the case of planar magnetic, a startling lifelike one!
Benefits:
- Sound enters your ears more evenly and naturally.
- Low distortion. The sound isn’t wobbly at higher frequencies.
- Large and powerful diaphragm. The surface area is such that more air is permitted to move with authority. This results in the most powerful and superior bass response out of any headphone.
- Responsive. The diaphragm is light and the force is strong. The ability for the signal to accelerate the diaphragm thus becomes better.
- They are easier to drive from an amplifier. Related: What is a Planar Magnetic Driver?
Check out Tyll’s Anatomy of a Planar Magnetic Headphone Driver
Angled Drivers
These are found in some higher-end headphones like the Beyerdynamic T1 and are angled to give you more of a theater-like presentation.
HIFIMAN headphones also tend to angle their drivers and sound best when the headphones are pushed forward so the back of the earcups are touching the backs of your ears.
- Recommended: 10 HIFIMAN Headphones Ranked From Worst To Best
The sound will start to come at you from the front, as well as all sides, thus improving Soundstage to a degree.
Ultimately, the difference is somewhat small, and they don’t replace true surround sound speakers by any stretch.
Still, open-back headphones with these drivers are known for providing a phenomenal Soundstage, and I can attest to it.
In other words,
you will hear a difference in 3D realism and the resolution may even improve a little.
Examples
Some examples of headphones with Planar magnetic drivers are the Audeze LCD-3, HIFIMAN Ananda/Edition XS, HIFIMAN 400se, etc.
Some examples of headphones that have angled drivers:
- Sennheiser HD 800
- Beyerdynamic T1
A great entry-level introduction to Planar Magnetic technology is something like the HIFIMAN HE400se.
It’s a superb sound and a definite eye-opening experience with the right equipment.
I remember the first time I heard Led Zeppelin’s Over the Hills and Far Away with the original 400i paired with the Bryston BHA-1.
It was one of the most realistic-sounding tracks I’ve ever heard, and to this day I still remember how lifelike everything was.
It was almost like the track was breathing and had a pulse of its own.
Final Word
Did I answer the question of: What is a headphone driver?
Let me know! I hope you’ve come away with some valuable information today, and have a better idea of how they function inside your own headphones!
Do you have any Questions? Comments? Requests? Did I miss something? Let me know below or contact me! I would love to hear from you…
All the best and God bless,
-Stu
