Pros: Among the most refined and detailed universal IEMs
Cons: Subpar clarity, obtrusive mids, missing forward projection
I've had the SM3 as a loner pair for several weeks, here's the summary of my impressions:
- Very refined sound reproduction
- Bass has top quality and just the right quantity for me
- Extremely detailed and attractive mids
- Almost equally good highs that never get too sharp
- Very realistic timbre for a balanced armature based phone
- Large Soundstage
- Excellent separation
- Decent isolation
- Very good cable
- Forward / in-your-face mids can be fatiguing with some music and/or prolonged listening
- Not among the best in clarity, highs are slightly recessed
- Only minimal forward projection of soundstage ("surround effect")
- Cable too short from earpiece to Y-splitter
- Only average wearing comfort
- Cheap and fragile looking housing
No beating around the bush, I have mixed feelings about the SM3. On the one hand I take my hat off to Earsonics for producing the most refined balanced armature based IEMs I've heard to date. On the other hand, the SM3's sound signature is a little different from what I was expecting after reading several rave reviews. They are slightly on the warmish side of neutral, and by switching between them and my other IEMs it becomes quite obvious that their mids are decidedly forward and in-your-face. In more than one way the SM3 strike me as a more sophisticated version of the SE530, a phone that I found absolutely stunning at first, but over time discovered that their sound signature was a bit too obtrusive for my liking.
Add in the SM3's unusual spatial presentation with only minimal forward projection of soundstage and the music occasionally coming from all sides, I'm sorry to say that as far as soundstaging is concerned, these strike me more as on-stage monitors than consumer IEMs.
Overall I think, even though the SM3 rightfully belong among the best universal IEMs I've heard, they are still a bit overhyped. They are a tad too warm and decidedly too mid-forward to be accurate. They have less clarity then a lot of other IEMs. Their soundstaging is a hit/miss/love/hate affair. Bottom line, if their sound signature fits your taste and you love (or at least don't mind) surround sound staging, the SM3 are for you. I didn't meet these requirements, so they were not for me.