Headphone drivers are the most important part of any headphones, as their quality and tuning determine the final sound quality.
Learn about:
- The headphone driver types
- Where you can find them
- Their technical characteristics
What is a Headphone Driver?
The headphone driver (or transducer) is a component responsible for producing sound. It converts an electrical audio signal into vibrations you can hear as music.
It is the most vital part of headphones and earbuds. Everything else, from design to other components, must ensure the drivers work as effortlessly as possible.
Headphone drivers are generally constructed from a:
- Magnet (typically made from neodymium, it interacts with the electromagnetic field)
- Voice coil (which creates an electromagnetic field)
- Diaphragm (which pushes air and creates sound waves)
Types of Headphone Drivers
The headphone industry uses at least 6 different types of headphone drivers. They come in various sizes and use diverse technologies to produce sound.
Each type has its strengths and weaknesses, so manufacturers sometimes combine different ones to get the best of both worlds.
Here are all the headphone types you might come across.
Dynamic drivers – moving coil
Dynamic drivers (or moving coil drivers) are by far the most common type of headphone drivers found in most consumer and professional headphones.
Dynamic drivers contain the following:
- Magnet (neodymium drivers)
- Voice coil
- Diaphragm
How dynamic driver works?
Electricity flows into the voice coil (a ring made of tiny, insulated copper wire), which creates an electromagnetic field. The coil is wrapped around the magnet.
By constantly changing the polarity, the magnet pushes the electromagnetic field (and the voice coil) up and down. Changes in polarity happen many times per second and depending on the frequency.
Since the voice coil is connected to the diaphragm, the latter also moves. By pushing air, it translates those up and down vibrations into sound.
Pros and cons of the dynamic driver:
- Dynamic neodymium drivers are the easiest and cheapest to manufacture.
- Moving coil technology is old yet perfected and offers excellent results.
- Dynamic drivers produce realistic, room speaker-like sound with deep, thumpy bass.
- It can be very power efficient, able to drive off portable devices.
- This type of driver is prone to distortion.
- Not the most controlled and detailed compared to other driver types.
Planar magnetic drivers
Planar magnetic drivers are used increasingly as a “cheaper” alternative to electrostatic drivers. You can find them in many audiophile headphones and even earbuds.
Planar magnetic drivers contain the following:
- Diaphragm with a thin coil
- Magnets
How planar magnetic driver works?
Diaphragm with a “built-in” coil is suspended between two oppositely aligned magnets. By changing the electrical charge of the diaphragm, the latter moves towards a specific magnet.
That creates movement, which pushes air and starts producing sound waves.
Pros and cons of the planar magnetic driver:
- Planar magnetic headphones offer more detailed and controlled sound.
- They are more expensive yet cheaper to produce than electrostatic drivers.
- Relatively easy to drive, even from a portable device.
- Larger drivers in size, which results in bigger earcups and heavier headphones.
Electrostatic drivers
This type of driver is rarely used in headphones, although you can find it in some expensive models. Its issue isn’t in sound quality but in price and difficulty to power.
Electrostatic drivers contain the following:
- A thin diaphragm from polyethylene terephthalate (also known as PET plastic) coated with an even thinner and electrically charged metal film.
- Perforated metal plates
How does an electrostatic driver work?
Diaphragm is suspended between the two metal plates, which act as electrodes and create individual electric fields when supplied with electrical signals.
The diaphragm then moves left and right towards the electrode, which produces an electric field. This movement starts to move air and create sound waves.
Pros and cons of the electrostatic driver:
- Electrostatic drivers can produce clear, full-range sound with great precision and control.
- The sound can be too clinical or “unnaturally clear” to some.
- Expensive to produce as even a tiny dust particle in the driver itself can result in audible distortion.
- Require unique headphone amps (electrostatic energizers) to run correctly (at least over-ear headphones).
Balanced armature drivers
Balanced armatures or BA drivers are found in in-ear monitors, wireless earbuds, and hearing aids.
Due to their small size, manufacturers can place multiple BA drivers into earbuds, each taking care of a specific frequency region (KZ AS16 Pro have 8 in each earbud).
Balanced armature drivers contain the following:
- Balanced armature (or a rod)
- Coil (wrapped around the armature)
- Magnet
- Diaphragm
How does a balanced armature driver work?
The coil is wrapped around the armature, which is fixed with a pivot and placed between the positive and negative ends of the permanent magnet. The armature also has one end attached to a diaphragm.
Based on the electrical signal, the polarity changes, seesawing the armature. That starts pulling the diaphragm, which begins to move air and produce sound waves.
Pros and cons of the balanced armature driver:
- Produce controlled sound with good detail retrieval.
- Small in size so that they can fit in devices like hearing aids, or one earbud can use multiple of them to achieve better sound.
- Energy-efficient, so you can drive multiple BA drivers in one IEMs from your smartphone.
- Not the best for full-range performance (although some great IEMs with only one BA driver exist).
- The bass response doesn’t sound as “natural” as with dynamic drivers.
Piezoelectric drivers
Piezoelectric drivers are used, although rarely, in earbuds and in-ear monitors, mainly to handle higher frequencies.
More than for headphones, this type of driver is used in stethoscopes, buzzers, sonar systems, seismographic measuring, etc.
Piezoelectric drivers contain the following:
- Piezoelectric material (quartz crystal or ceramic)
- Diaphragm
How does a piezoelectric driver work?
Using the principles of electronegativity and molecular dipole bonds, piezoelectric material can shrink or stretch depending on the polarity of the voltage.
That tech uses shrinking and stretching movements to move a diaphragm, which displaces air and produces sound.
Pros and cons of the piezoelectric driver:
- Sensitive to small changes in voltage.
- Suitable for producing higher frequencies.
- Not suitable for full-range response due to weak bass output.
- Occasional sizzle in high frequencies.
Magnetostrictive (bone conducting) driver
This type of driver only vibrates and doesn’t displace air, making it an ideal pick for bone-conduction headphones.
Magnetostriction transducers contain the following:
- Plates made out of magnetostrictive material like nickel
- Wire coil (conducting coil)
How does a magnetostriction driver work?
Multiple plates are placed in parallel and with one end attached to the surface to transfer mechanical vibrations. Wire coil goes around the plates.
When sending an electrical current through the coil, it creates a magnetic field, which interacts with magnetostriction material, causing plates to stretch and shrink.
That creates vibrations that transfer to the headphone’s surface, your cheekbones, and later to your middle ear.
Pros and cons of the magnetostriction driver:
- Suitable for bone conduction headphones for people with external ear damage.
- Bone conduction drivers have a low quality sound.
- You need large transducers to produce some bass.
Comparison of Headphone Driver Types
| Sound quality | Impedance & sensitivity | Size & weight | Price | |
|---|---|---|---|---|
| Dynamic | Excellent but prone to distortion, natural bass response | Low impedance & high sensitivity, but not always | 6mm to 70mm & moderate weight | Cheap to quite pricey |
| Planar magnetic | Excellent and controlled, not as natural bass | Low impedance & sensitivity around 100dB, but not always | 12mm to 110mm & heavy | Pricier than dynamic |
| Electrostatic | Excellent and controlled, but the bass isn’t very powerful | Higher impedance & high sensitivity, but require special amps to power | Up to 120mm & heavy | Expensive |
| Balanced armature | Great and controlled, but limited in the frequency range, not as natural bass | Low impedance & high sensitivity | Small & light | Pricier than dynamic |
| Piezoelectric | Good and clear but not as detailed, with some sizzle in cymbals | High impedance & high sensitivity | Small & light | Relatively expensive |
| Bone conducting | Decent but lacking detail and bass response | Low impedance & high sensitivity | Around 16mm & relatively heavy | Pricey but not expensive |
Other factors to consider when choosing headphone drivers
TYPE OF MUSIC
If you seek natural, warm sound with all its flaws (some people actually prefer that for casual listening), dynamic drivers are the best. They’re especially great for bass-oriented music, like electronic, pop, reggae, classical, and rock.
On the flip side, electrostatic, planar magnetic, and balanced armature drivers shine when it comes to precision and detail, offering better sound quality. They’re great for more analytical listening and all kinds of genres apart from bass-forward ones.
Piezoelectric drivers work fine with most genres except aggressive ones like metal, where loud cymbal crashes cause sizzling.
Magnetostriction is suitable for music with little instrumentation, as it cannot keep up with busy tracks.
COMFORT & FIT
This really depends on the size of the drivers and the type of headphones. Earphone drivers don’t impact comfort in earbuds and IEMs, since they’re always small.
But for bigger headphones, planar magnetic and electrostatic drivers can be massive. Therefore, expect the headphones to be heavier and less comfortable than other options.
DURABILITY AND PORTABILITY
The only driver type that suffers from portability is electrostatic—however, only the one in over-ear headphones since you need special energizers to power them correctly. The ones in IEMs also work with portable devices.
On the other hand, no particular driver type is more susceptible to durability issues than others. But if we must pick, electrostatic headphones are the most sensitive and require the most controlled manufacturing.
BRAND REPUTATION
Most manufacturers make their own driver designs, so the quality varies depending on the model. One example of a reputable brand that indicates quality drivers is Knowles, which makes balanced armature drivers.
Do headphones with more drivers mean better sound?
Headphones with more drivers don’t necessarily sound better than the ones with one driver that’s masterfully tuned.
If anything, we’re seeing that earbuds with dynamic/BA combos usually sound bright and unnatural. As if they’re trying to sell the fact they have two drivers and not their audio quality.
So don’t let the number of drivers fool you. Especially if you’re looking at multi-driver gaming headsets, which are a pure gimmick.
That said, many high-end IEMs have multiple drivers, and even musicians use such IEMs as monitors during their performances.
Are bigger headphone drivers better?
Bigger headphones drivers can output a more natural, room-speaker-like sound. But don’t confuse that with sound quality or bass response.
As long they’re properly tuned, even smaller drivers can deliver high-fidelity sound with excellent detail. They can also produce bass-heavy, skull-rattling sound.
On the other hand, bigger drivers displace more air and create a more natural feel.
Frequently Asked Questions (FAQ)
Which driver is best for headphones?
Planar magnetic or electrostatic drivers are the best for headphones if you want controlled and detailed sound. However, dynamic drivers also sound fantastic and even more natural in the bass region.
What drivers are used in headphones?
Drivers used in headphones are dynamic, planar magnetic, electrostatic, piezoelectric, balanced armature, and magnetostriction. The first three are used in full-sized and in-ear headphones, 4th and 5th are found in IEMs, and the last is used in bone-conduction headphones.
How do I find my headphone driver?
You can find your headphone driver type by looking at the packaging, specifications, or official website. Some brands only tell you the type, but in general, you also learn about the size and materials used to make a diaphragm.
Are 40mm drivers good for gaming?
40mm drivers are perfectly good for gaming, even if you want extra bass oomph. The most important thing isn’t their size but their tuning.
Conclusion
Headphone drivers are an essential part of all headphones and earbuds. Using different types or the number of drivers, manufacturers can achieve the desired level of performance.
But remember that tuning is more important than just the driver’s type when listening to music. So don’t discard or prefer a specific type just because it has a higher potential to sound better.
From a childhood fascination with sound, Peter’s passion has evolved into a relentless pursuit of the finest headphones. He’s an audio expert with over 5 years of experience in testing both audiophile and consumer-grade headphones. Quote: “After many years, I can confidently tell which headphones are good and which are terrible.” Find his honest opinion in his reviews.
