Different Types of Drivers Used in IEMs
Every earphone, headphone, and speaker systems feature different driver units that some people call “sound transducers”. Sound transducers are the backbone of your sound output; the better the transducer quality (and tuning), the better the sound output. There are several types of different driver units that are commonly used in in-ear monitors, namely, Dynamic Driver unit, Balanced Armature Driver unit, Electrostatic Driver unit, and Planar Magnetic Driver Unit, among some other obscure ones. Apart from putting a single driver unit, brands also make multiple driver units in which different areas of the frequency range are handled by different units. Today, we are going to discuss all these driver units, how they work, and, pros and cons. The pros and cons presented here are my subjective opinion so your mileage may vary. So let’s begin.
1. Dynamic Driver Unit (Moving Coil Driver Unit):-
Dynamic Driver is also known as a moving coil driver unit. A dynamic driver unit consists of three main parts, a neodymium magnet, a voice coil, and a diaphragm that is connected to the voice coil. Voice coil is a thin membrane that moves in a stationary magnetic field generated by the magnets in the driver unit and hence produces the sound. The membrane is usually made up of copper material but in high-end headphones/earphones, more premium materials are being used like beryllium and more. It gains the magnetic field once the current from the input signal is passed through it. The airwaves created by this movement of the voice coil is then taken by our ears as sound. Dynamic driver units produce a powerful sound output that features quick and deep bass response. The driver produces outstanding details in the lower end with its snappy coil movements. Over the course of developments in the audio industry, dynamic drivers are widely used in hybrid IEM’s to handle the lower end effectively and efficiently. Dynamic drivers vary with different size, they are widely used among full-size over-ear headphones too.
Pros of Dynamic Driver Units:-
>The manufacturing cost of dynamic driver units is fairly cheap as compared to other driver types.
>Dynamic driver produces sound by moving air resulting in powerful bass reproduction.
>Dynamic driver units have low power requirements and can be powered very easily.
>They are quite versatile and can be used in multi-driver hybrid setup IEM’s.
Cons of Dynamic Driver Units:-
>Since the sound is produced by moving units, there are more chances of distortion in dynamic driver units.
>They are quite big as compared to other driver types.
>With a thin membrane these drivers are susceptible to driver flex, a stretching sound that comes while pushing the IEM’s into the ears.
Latest DD driver IEM:-
DUNU Luna is the latest flagship IEM from the brand that features a whole beryllium construction. Not only the driver unit but the whole ear shell is made up of precious beryllium material. The design here is inspired by Moon’s landing 50 years ago and the ear shells represent the moon’s lunar surface. It produces a reference level of high quality sound output. The DUNU Luna is a flagship-level IEM and it comes with a lot of accessories included in the package, it features two leather carry cases, multiple pairs of ear tips, including custom made SpinFit ear tips, and much more. The main attraction of the package apart from the beautiful earpieces is a pure Furukawa single crystal and DHC Pure Silver mixed hybrid modular cable that comes with multiple connector plugs including 3.5mm single-ended, 2.5mm balanced, 4.4mm balanced, and a 3.5mm balanced plug. The whole package comes at a price of 1699$ and surely is one of the must have’s for a reference level extraordinary sound quality experience.
2. Balanced Armature Driver Unit (Moving Iron Driver Unit):-
The balanced armature driver units are also known as moving iron driver unit. These units are very small and are only found in in-ear monitors. The driver unit consists of a miniature arm in a coil of wire surrounded by two magnets that create a magnetic field when the current from the input signal reaches the driver. The moving part is balanced between both the magnets that’s why the drivers are called balanced armature drivers. The armature moves slightly towards the poles of permanent magnets with the magnetic flux created by the audio signal. This movement of the armature unit brings changes to the air above the driver diaphragm that provides the sound output. BA driver unit has very little movement compared to the dynamic driver units and thus produces no distortion in the sound output. BA drivers are very power efficient and can be driven very easily, due to their small size multiple BA driver units can be put in a single pair of IEM’s producing precisely detailed sound output. BA driver unit produces natural vocals and smooth detailed treble responses.
Pros of Balanced Armature Driver Units:-
>BA Driver units can be tuned precisely for desired frequency ranges and are of very small size, making it possible to put multiple drivers in a single pair of IEM’s with precise tuning to provide a more detailed sound output.
>Since not much movement is involved the output is free from any kind of sound distortion.
>These are very power efficient and need very little power to produce an amazing sound experience, so very easy to drive.
>More detailed and better treble extensions as compared to the dynamic driver units.
Cons of Balanced Armature Driver Units:-
>BA driver units are very sensitive and might produce hissing background noise.
>BA driver bass response is usually slower as compared to dynamic driver units.
>A bit expensive to produce as compared to the dynamic driver units.
Latest BA Driver IEM:-
Moondrop is a China-based earphone equipment brand. The brand produces some brilliant pairs of IEM’s with precise tuning and brilliant looks. The Moondrop S8 features 8 BA drivers each side tuned precisely to produce a well detailed sound output. The pair not only produces a lifelike natural sound output but also has brilliant looks with transparent ear shells. The pair shows a well extended lower and higher-end producing precise micro details and no sound distortion. It comes with a 6N OFC cable and a beautiful carry case. The pair is built exquisitely with outstanding craftsmanship, you can grab this pair for a price of 699$ from various stores on Aliexpress, the Moondrop S8 produces a balanced and natural sound that can compete with multiple hybrid driver IEM’s priced way above it.
3. Electrostatic Driver Unit:-
Electrostatic drivers(EST Drivers) have been here for a long time for high-end full-size cans, but the technology has been developed for IEM’s. Now we have got very small EST drivers that don’t require separate energizers as required in those over-ear cans. An EST driver works on the principle of static electricity, moving an ultra-thin membrane(Diaphragm) between two electrodes. The diaphragm moves swiftly between the electrodes producing unmatched detailed sound output. EST drivers produce a brilliant treble response with great extensions and smooth details. They produce precise micro details with no signs of harshness or sibilance. The movement of the ultra-thin diaphragm is very swift and smooth, there is no distortion in sound output through the EST drivers. These drivers are small and lightweight, hence they can be used in hybrid driver IEM’s. Previously EST drivers are used to be huge and required energizers to power them in full-sized cans, but the latest technological developments have made it possible to put the technology in small driver units.
Pros of EST Drivers:-
>Offer small size, easy for implementing in hybrid setup IEM’s.
>Unmatched Treble response with excellent details.
>Natural Timbre and Instrument Tonality.
>Able to produce a wide soundstage.
Cons of EST Drivers:-
>EST Driver units are power-hungry as compared to other driver types, they shine with better and powerful sources, on less powerful sources say your smartphones they won’t perform with their full potential.
>EST Drivers are expensive and currently found in high-end IEM’s.
Latest EST IEM:-
Kinera is a brand that produces brilliant IEM’s at all price ranges, their products carry outstanding looks and soothing beautiful sound output. The Kinera Nanna is the flagship pair of in-ear monitors from the brand, it features a multi-driver hybrid unit featuring One Dynamic driver unit, One Balanced Armature unit, and two EST driver units. The pair produces an excellent sound quality with a wide sound stage and extended lower and higher end. It looks outstanding with a premium build and exquisite design. The pair comes with a pure single crystal copper cable and a lot of accessories including carrying case and more. Kinera Nanna has a rich with crisp sound output, the lower end has a full-body bass response and excellent sub-bass rumble. The mids BA produces lifelike natural vocals, and the two EST drivers produce an articulated treble section rich with details. The pair suits well with any genre of music with its neutral tuning and wide sound stage. It is priced at 899$, and available at Hifigo.com and various aliexpress store.
4. Planar Magnetic Driver:-
Planar magnetic drivers work on a similar principle as that of a dynamic driver unit though instead of using a moving coil between the magnetic field, the planar magnetic driver uses an ultra-thin membrane(Diaphragm) to produce the sound output. These drivers have been here in full-size drivers for a long time but recently they are coming in IEM’s as standalone or hybrid drivers. Planar magnetic drivers produce a natural and life like a vocal response, and good details in the treble region, with a well detailed controlled bass section. Output through planar magnetic drivers is well balanced and neutral. These drivers demand extra power and shine with high-quality sound output with that extra power.
Pros of Planar Magnetic Driver:-
>Lifelike natural sound output.
>Excellent Bass and sub-bass characteristics.
>Very low distortion.
Cons of Planar Magnetic Driver:-
>Planar Magnetic Drivers are expensive.
>They need extra power and produce a dull output with less powerful sources.
>Usually large in size as compared to BA and DD driver units.
Latest Planar Magnetic Driver IEM:-
Tri i3 is the latest pair of in-ear monitor with a three-driver hybrid setup on each side featuring one planar magnetic driver, one composite dynamic driver unit, and one balanced armature unit. The pair has a rich build with large ear shells made up of CNC aluminum alloy material. It produces a life-like powerful sound output with deep thumpy bass, natural vocals, and a smooth detailed treble response. The pair performs exceptionally well and outperforms various other pairs of IEM’s priced way above its price. Tri i3 comes with a handful of accessories including a velvet carry case, SPC MMCX cable, and more. It is available for just 169$ at various aliexpress stores, and we really recommend it if you want to try out planar magnetic driver earphones at a budget. But be aware to use it with some power source to make it shine with all its strength.
That is all the different types of drivers currently being used in the IEM’s. Dynamic and Balanced armature drivers are the most widely used in IEM’s. They are there in IEM’s in all price range in all types of driver setups, whether it be single driver IEM having a single BA or single DD unit, multi-driver IEM having multiple BA’s, or even hybrid driver IEM’s with DD and BA cross over. EST and planar magnetic drivers are currently available in mid to high-end pairs of IEM’s, though a few single EST and Planar magnetic driver IEM’s are also there in the market like Shuoer Tape, Tin Hifi P1. Both of these are budget IEM’s and comes under a 200$ price range. With the constant development in the China audio industry, we are really hoping we will see budget IEM’s with EST drivers in hybrid setup soon.