Here are my impressions of the UERM compared to the ER4S. My Etymotic ER4S cable is broken so I can only do comparison from memory.
- Sounds somewhat warm without EQ. Emphasized lower mids and peak at 10KHz.
- Thicker bass texture than ER4S but similar emphasis and bass extension
- Treble extension not as good as ER4S. About the same treble extension as ER4P.
- Similar soundstage as ER4S
- Mids are better than ER4S, less resonances and no 3KHz peak.
- ER4S might have slightly better detail, mainly in the treble and upper mids (will need to do side by side comparison to confirm)
- Perfect fit and comfort. Most comfortable IEM ever.
- Similar isolation as the ER4S with small triflange tips
- I think I should have ordered the JH13 FreqPhase instead. Details and soundstage are better than both the ER4S and UERM (from what I recall from the universal demo). The JH13 is not neutral but if I'm going to use EQ anyway, might as well go for the more detailed IEM.
Conclusion:
Overall, the sound quality is almost on par with the ER4S. It's better than the ER4S in some areas (thicker bass, less peaks, no 3K resonance), but worse in other areas (treble extension, treble and upper mids detail). Isolation is the same but the UERM has far better comfort.
EQ I'm currently using with the UERM: