Well, if it may be of any help (sorry, I'm not really familiar with sound description in english).
Earsonics, one of the major agents on the market in universal and custom IEMs for professional and retail, sells, since 2004, highly prized products.
The flagship, EM3-PRO came out in 2006, with 3 drivers / 2 ways technology, still being considered as a reference, suffered from competition with new technology and their own flagships.
Earsonics' philosophy was not to take part in the race for number of drivers just to impress and fill technical data, but is more looking into delivering the most "accurate"/life-like reproduction of sound, which is what technology was created for.
Nonetheless, the company had to show it could face competition, being up-to-date, technologically speaking, but using it to express it's vision of what sound reproduction should be.
Thus, the EM4 with its 4 drivers / 3 ways.
Once again, Earsonics offers a very simple packaging, without any superficial accessory.
Acrylic box, cleaning tool (a Pelican or Otterbox would have been great).
Let's first explain how this product was created :
Impedance, sensitivity and need of power :
- 4 drivers / 3 ways : home made, not similar to competition.
- As one of the drivers needed air, the IEMs are not filled fully, that driver being separated in an empty part of the IEM (but still the shell is thick enough not to break), allowing future upgrades.
- These should be fine on any setup : they worked on impedance and sensitivity. Higher impedance and higher sensitivity than usual so that "weak" DAPs will not lack bass (and to increase DAP's autonomy)
- Working on stability of impedance with power : being able to sound great on amplified setups, listening at high volume without distortion or tonal imbalance.
Balance of spectrum
- clean and "tensed" lower-mids, for a deeper and clearer reproduction (the last octaves of low frequencies not being covered by the low frequencies for a more organic sensation (don't really get this part...)). Clarity in mid-mids for a listening experience close to full-size headphones.
- High-mids home-made (like other Earsonics IEMs), never being aggressive, being at their right place.
- Highs are thin and extend high for a more natural texture, closer to full-size dynamic driver.
- Larger soundstage, out of the head, and more frontal (thanks to a specific work on spectral balance, and respect of phase, using a home-made process to make the stereo image more airy)
The EM4 are aiming to be Hi-Fi and balanced, with warmth and being full-size-like organic.
It is a kind of mix of the spectral dimension of EM2 and EM3 (the benefits from both united in the EM4) with a new spatial presentation, more full-size (more airy, larger stereo image)
Player : Studio V (Wave files) + iBasso Pelican PB2
I had the chance to listen many times to Earsonics products, and the EM4 tickled my curiosity. But I was worried about the loss of the so particular sound of Earsonics, because of the tendency on acoustic signature.
I was soon reassured by finding the Earsonics particularity in sound, even before interviewing the constructor. It was the perfect mix of EM2 and EM3-PRO, and the name, though simple, fits it.
The will for details, the rigour of the EM2, the warmth and spatialization of the EM3 all concur to a very well finished EM4.
Thus a very high definition, astonishing details, and I'm weighing my words.
Sounds stream out in space with impressive intensity, accuracy in reverb and spatial placement.
The high sensitivity of these IEM allows to hear the ending notes much longer than on any IEM I heard.
Air literally flows between instruments.
Added to a tonal accuracy across the whole spectrum, you get "hitting" bass, with "skin" presence (I don't really get that part...), very natural mids/higher mids that point out every detail in vocals, and "Lopezian" highs (I guess these are Franck Lopez special/Earsonics highs?) that already satisfied many users, but for those who have already heard EM3-Pro, try to imagine even better, with an increased dynamic, and even higher resolution.
Soundstage has not been spared either : soundstage is larger, but mainly in depth, vocals are forward (it has already been mentioned with EM3, but here it is so well mastered).
However, a tendency becomes reality : bass-heads should pass... No over-boomy bass, no "feeling" of the bass. These are more for people looking for a very accurate reproduction, IEMs that transcribes music with a big M (don't really know what he means) without any other consideration.
EM4 has raised the bar very high. A great ability to create a natural atmosphere.
A very realistic soundstage, in width and depth. I had never heard such a soundstage before.
Bass revealing a "skin" aspect, giving the sound an organic reproduction.
One of the best (if not the best) ability to transcribe the notes extinctions due to the extreme sensitivity of EM4.
A very extended frequency response.
IEMs that are the perfect mix of EM2 and EM3-Pro, allowing musician and music-lover to both enjoy these.
Only con : the very high cost of these, willing to provide a 100% "Made in France" product. This spoils a bit the experience, but if you can afford it, you won't regret it, just go. It is rare to find such an expertise in a sole IEM.
Subjective dynamic : 5/5
Timbre accuracy : 5/5
Quality/price ratio : 4/5
Global rating : 4,9/5
Link to the test (in French) : http://www.tellementnomade.com/earsonics-em4-le-test/
Edited by Damnegy - 11/7/11 at 1:33am