I have been gravitating more to IEMs this year. I have been listening to ALAC encoded music on my iPhone. Interestingly I am listing less and less to my HD650 balanced rig.
I have tried the the following portable setups:
1. Ety ER4p - Great detail and midrange, but recessed bass. Superior isolation. Used Dance EQ setting on the iPhone to get some more bass out of them. The Bass Boost EQ setting results in distortion so I don't use it.
2. Ety ER4P - With FiiO E5 amp bass boost on, and the Etys sound much fuller and richer... still a bit bass shy.
3. Ety ER4P - With Minibox E+ PtoS on P and bass boost on, and the Etys sound even fuller and richer... still a little bit bass shy but now to a point that you would really be nit picking. An impressive performance but bulky carrying around an iPhone and an amp.
4. Westone 3 - Unamped from an iPhone... where did all that bass come from? In fact it so bad that I have had to use the Acoustic EQ setting on the iPhone to get some of the midrange back. Vocals too recessed for my taste. Amping the W3s brings back more of the midrange.
5. Westone UM3X - Wow! This is more like it, an even sound signature and now decent midrange... all this and I have not amped them. This is giving me a comparable sonic experience the the Minibox E+ and the ER4Ps, yet I don't need to lug a portable amp with me. Outright the Minibox E+ amped ER4Ps still rule for midrange and vocals but the unamped UM3Xs are very close. Overall, the UM3Xs offer a more balanced sound and do this without amping. The UM3Xs are also a bit smaller the then W3s and isolate a bit better too. Amping them improves them again but I can live without it. A word of warning the UM3Xs will show up poor sources and low bitrates more than the W3s.
The Westone UM3Xs are the best IEMs I have tried... now I'll try the UM56 custom tips to see if they work better then the Complys.