On A4000, starting at around 0:01, I hear the drummer making what sounds like 2 circles on the snare with brushes which I hadn’t paid attention to on ER2XR. Once I knew it was there I could faintly hear it on ER2XR as well and by increasing volume I could hear it clearly but at the expense of making everything louder.
The piano sounds warmer, fuller and rounded/blunted on A4000 while on ER2XR the attack is more defined/sharper, has nice decay and sounding tonally richer and more “real” (actually sounds like piano keys being struck).
On A4000, cymbals and hi-hats sound more emphasized, splashy and have a lot of sizzle, drawing attention to them in the mix while on ER2XR they are just there, are more articulate and cymbal strikes actually sound like wood (drumsticks) hitting metal.
The upright bass is more emphasized and has more body and mid-bass on A4000. It stands out more in the mix than on ER2XR.
Imaging seems more precise on ER2XR, for example with the piano and especially on hi-hat, cymbal strikes and snare hits.
While the instruments seem to be panned to similar width on both IEMs, on A4000 the cymbal strikes sound closer and higher. I assume this is because of the boost in the highs. The A4000 also has a larger “sense of space” (wet/reverb).
With ER2XR, the piano is the star of this track (which is how I think it’s mixed), while on A4000 the trio seem to be fighting for attention. The A4000 has what I call “emphasized detail” on this track where certain sounds/instruments are emphasized (which might make it interesting for some people) at the cost of tonal richness and sounding “natural”. This track is more engaging, immersive and richer on ER2XR for me.
These measurements are made on my DIY IEM measurement rig and are not accurate, and don’t necessarily represent what you might hear, especially before 60 Hz (huge sub-base roll-off) and after 10 kHz (and maybe even after 3 kHz as my ER2XR graph is very different compared to Crinacle’s post that). You can use it just to get a comparative idea, hence the comparison with ER2XR to give you a point of reference. Improving the rig is an ongoing process.
Here is Crinacle’s ER2XR graph for reference
It looks like final went with the mids to bass rise like in the E series and the highs of the A8000 on A4000.
While reviewing the Etymotic ER4SR and ER4XR here is what Tyll had to say about bass response:
For me, the bass level on the ER4SR simply isn’t enough. Frankly, even the ER4XR doesn’t have enough bass for me, but it’s much better. I believe quite strongly that bass response on headphone should have about a 5dB bass boost below about 150Hz.
When the ER4XR was launched, Tyll applauded Etymotic for making the brave move of catering to user preferences and deviating from that they believed to be technically “accurate”. I think Etymotic went further with the ER2XR (and it’s almost like they took his feedback into account) and for that I am grateful as the ER2XR has just the right bass response for my preferences 🤗.
For me, having over 20 years of close experience interacting with Etymotic and the ER4 product evolution, I find it an interesting example of corporate learning at work. On the one hand, Etymotic has very strong reasons to believe they have a grip on what “accurate” means, on the other, they have 20 years of experience with customer feedback about the desire for more bass. Adding bass willy-nilly is simply not something this audiometry company would do; but having strong feedback that customers want more bass can’t be denied either. Making the corporate decision to deviate from technically accurate to cater to user preference is actually a pretty brave move from their point of view. I applaud this development!