Pros - Width and deepness : soundstage / smooth signature / perform at low volume
Cons - lack of treble extension / textured but lack of thickness / source sensitive
EarSonics is a french CIEMs and IEMs manufacturer that is based in the south of France, near from Montpellier. All the prices are also in €uros.
The EM4 are based on Franck Lopez thoughts after the EM3pro. They gain in width, clarity, separation and precision. But they are not made for guigs, you can use it for but it's not especially done for. I would advice to take the EM6 for. They are enough sensitive to be used on DAP and enough resistant thanks to its relative high impedance. You could hear hiss but it's not as annoying as with lower impedance CIEM. 4 drivers, with 2 TWFK for the mids and highs and 2 CI for the lows in a 3 ways configuration.
The low are extended, with smoothness. The impact is soft and you can seem that it lack something dynamic in the bass-mids. But the characteristic is a quality that allow the EM4 to be permissive on poor tracks and soft on very speed tracks. If you love bass impact and speed, pass this one though they don't lack of dynamism.
The mids are creamy, sometimes given the feeling of veiled, but they keep clarity at a good level. Furthermore they are very musical and know how to convey emotion. Indeed the EM4 are mid-centric earphone and the mids are not as laid-back as the other freqs. Nevertheless those who are sibilance fans would be dispointed, clearly here you have to move on.
The trebles are laid back and lack of extension especially on poor tracks. They are liquid and very smooth but they lack of harmony and can't convey emotion as the EM6 or EM32.
I like the soundstage of the EM4 that push forward the instruments. Nothing sounds near the ear, all is forward your eyes. It brings the feeling to be in the public during a concert.
I would advice people that love trip hop / ambient / female vocals / ... could love the EM4.
Those who love metal / rock / etc. could prefer the big brother, the EM6, that to my mind are different but not better.