What are Balanced Armature Drivers in IEMs?

Inexpensive IEM headphones for Audiophiles on the move

Simgot’s EM6L ‘Phoenix’ headphones are a £104 / $110 update of their earlier EM5 IEM (In-Ear-Monitor) which feature a hybrid arrangement to their drivers – an 8mm Dynamic Driver, working on the same principles as conventional dynamic drivers in speakers with a voice coil connected to a driver and arranged around a magnet system, and two sets of Balanced Armature drivers. Hence why the brands spec states ‘1DD + 4BA‘, with the latter being a type of driver often used in IEMs with a relatively narrow frequency range. Also, why you often see multiple BA drivers within IEM headphones, and particularly because the small size of the diaphragm tends to suit use for high frequencies. With the EM6L’s the dynamic driver covers the lowest of frequencies and the armatures, for the mids and high frequencies. Because of the multiple drivers they use a 3-way crossover.

The principle of operation of a BA is one where an armature is wrapped in a conductive coil placed between two magnets in an enclosure, normally a metallic one. When an audio signal is applied to the armature the electromagnetic properties of the armature cause it to move. Remember Faraday’s law! An associated attached drive pin then moves a diaphragm that creates sound waves which are emitted from a sound hole. These balanced drivers often look similar within different IEM’s, having a loose appearance of the shape of a bottle laid flat with the neck constituting where the sound hole narrows.

These IEMs are made up of a resin 3D printed enclosure (essentially a means of CNC machining) channelling the drivers into independent internal tubes, with aluminium faceplate inserts and a gloss finish. If you’ve never tried these types of IEM’s, their shell shape in fitting into the ear’s ‘concha’ – the hollow area before the external auditory canal leading to the ear drum, is conducive to stopping sound from your environment. I’ve found them particularly useful walking around London’s traffic with my Chord Electronics Mojo2/Poly combo. This is in difference to bud type IEMs which don’t have such inherent noise isolation. Also a useful purpose of being this shape means they stay in place. I found them very comfortable with assorted shape tips included – they do take practice at getting your head around fitting them in place with the way the wires curve around the ear, if you’ve never tried these types before. That’s if you are like me and have no issue explaining complex thoughts, but you might not be the greatest dexterity contestant on the Krypton Factor.

You do get a nice plastic hard case and the cable is of the silver plated oxygen free copper (OFC) variety and the 2-pin connectors they use are referred to as being of the QDC type.

They have been designed for the Harman 2019 target curve which the brand say means a natural soundstage, and expansive audio field. I found this particularly true on trying so it’s no marketing BS. Essentially this curve is the one I’ve shown, which was designed by Harman engineers and essentially involves elevated bass and treble and apparently has gone through various iterations based on blind tests of what individuals prefer.

I wouldn’t describe the EM6L sound as bright but as ever that’s often a negatively constructed oxymoron of a description, to anything that is resolving or detailed. Though there is an element of subtle extension in treble and this is clear. It isn’t fatiguing I would add, so I think the treble characteristics of these headphones are wholly suitable and not atypical.

However staging capabilities are good and imaging and separation of sounds is accomplished and this is one of the most obvious characteristics of these IEMs and for buying perhaps their ratio decidendi…or reason for deciding. Once you appreciate the treble comes extended into a broad canvass of a soundscape and you’ve done ‘time on listening ear adjustment’, you start to appreciate their character more and the way the treble meshes into the broad shouldered way they sound.

In comparison to some more expensive $300 MAS Audio Science X5i’s which use a similar configuration of a 10mm dynamic driver and 4 BA drivers, the sound is more nuanced and expansive with the Simgot’s. The X5i’s are comparatively warmer and more muscular with bass as you might expect with the 10mm (versus 8mm) dynamic driver. But some of the staging has gone to the EM6L’s and the balance of the bass might not be for some with the X5i’s.

I intend to give products like these to Patreons and I have asked about trying Simgot’s more premium EA1000 IEMs which retail for $200. Both to compare to these before doing so and in order to make a meaningful comparison as well. If you want to be in for the chance to win products like these, please make sure you sign up to mu Patreon here : it is low cost at only £$€ 5 a month, and I give extra thoughts and comparisons there and it helps support me.

These are not crazy prices but these EM6L headphones perform well and I think are testament to the fact, being mainly a lounge based audiophile myself, that you don’t *necessarily* have to spend lots on IEMs to get good performance.….. these Simgot EM6L headphones are recommended if you want an involving pair of inexpensive IEM headphones with a wide spacey detailed sound to be out and about with whilst offering good sound shielding. Whilst these types of inexpensive headphones are not what I would usually review to my traditional HiFi based audience, I’m glad I did as I’ve really got into them and have used them lots!

Specifications (from brand website)

Driver Configuration : 1DD & 4BA
Dynamic Driver : high performance polymer composite diaphragm & dual cavity driver
Impedance : 26ohms +-15%(1kHz)
Sensitivity : 199dB/Vrms (@1khz)
Frequency Response Range : 8Hz-40kHz
Effective Frequency Response : 20Hz-20kHz
Headphone Jack : 0.78mm 2-pin
Shell process : high precision resin 3D printing
Wire material : high purity silver plated OFC wire.