I have 2 sub $100 IEMs, the ADDIEM and the NE-7; the ADDIEM I just got is used. My thoughts on both:
- NE-7 mic sounds better to people on the other end
- NE-7 is less microphonic (however, I wear the ADDIEM over the ear, which allows a good insertion angle)
- NE-7 is easier to fit (I am using the stock silicon tips, with the ADDIEM I am using Shure olives)
- NE-7 has more/sometimes boomier bass (but I only noticed it on a few tracks, maybe it is hitting a resonance frequency in those songs?); NE-7 plays 16Hz test tone, can't hear before 20 HZ on ADDIEM (next step is 25 Hz, which is at a lower level than above freqencies)
- NE-7 has a warmer, more bass oriented sound signature
- NE-7 is more sensitive, requiring a lower volume setting for the same playback level
- ADDIEM is a little more detailed
- ADDIEM has better instrument separation by a lot
- NE-7 is smoother sounding
- ADDIEM is worn much deeper in the ear canal; I wear the NE-7 in the outermost part of my ear canal
- ADDIEM has a more 3-D headstage as one of the NE-7s biggest weaknesses is a compressed 3-D headstage
- The above sound comparisons are when critical listening, when listening casually, there is little difference to me other than warmth (and that is not all that big)
What are the best sub $100 IEMs? The ones that fit your ears the best, are comfortable, and have the sound signature that you like. I have come to the conclusion that IEMs sound very different to different people due to fit (ear placement and seal), and some people try harder/have more experience getting a proper fit for them than others.
IMO both the NE-7 and ADDIEM are great, but with slightly different strengths. Which I prefer depends upon the music. The NE-7 has my preferred sound sig and sounds more natural to me on some music, and I like the additional bass. But there are times the ADDIEM is preferred, such as when songs have great 3-D soundstages (like ATB), or the bass is too boomy on the NE-7 (like Hotel Califorina from Hell Freezes Over). Also, using the E5 with bass boost for the ADDIEM makes the bass a little closer to the NE-7 and the sound is warmer.