Pros: Detail, balance, transparency
*This is a review for the EB (Extended Bass) version, not the original*
The Shroom EB's use micro drivers that sit inside your ear canal instead of just outside like most IEMs, the drivers are physically smaller and this means that the Shroom has a very small housing. They fit without touching most of your ear and can be worn cable up or down. The barrel is relatively long so it will stick out a bit and won't disappear in your ears so sleeping with them won't be comfortable. Isolation is good without needing deep insertion atlhough the drivers are located very close to the tip of the earpiece nozzle so keeping it clean could be a problem.
The strain relief on the housing is slightly unorthodox but does the job, the one on the jack is not so confidence inspiring. The cable is rubberised and tangles quite easily and is also microphonic but this is not a big issue if worn with the cable routed over the ears. Build quality is average.
The detailed sound is the biggest draw for this earphone and it comes closer to my RE0 than I would have expected given that I paid half as much. It has a very flat and balanced sound sound to it that emphasises nothing to the point that they are slightly boring. Treble is crisp and clean, the midrange is detailed and neutral and the bass is quick and textured but those small drivers don't move enough air when needed. I though the RE0 was poor in this area but the Shroom is worse. My M6 has plenty of punch but sounds boomy in comparison so the quick and clean bass and this makes up for the lack of slam eventhough I would have liked more extension. I own and enjoy the RE0 and AT AD-900 so the bass quantity is fine for me but they might be bass-light for some.
I listen almost exclusively to alternative rock and I wouldn't say the Shroom is poor at this genre but it is definitely not the best suited. They don't have the dynamics to convey the energy in the music and it can come across as boring. I don't listen to enough of the other genres to say how they would perform at those.
Overall, they sound very good for the money and handily beat the Meelec M6 which I bought for the same price in almost all technical aspects of their sound but the Shrooms have an unusual sound signature which can be quite uninvolving.