Here's my take on the RS2e vs RS1i. Buckle up, it's a long read.
* Sound signature:
The overall character of the two is similar. I find the treble is about the same between them. The difference is that the mids are fuller on the RS2e, which may give the impression that they're less treble heavy, but they're every bit as bright. Vocals and other sounds in the upper mids sound a little more natural because of this increased fullness.
In comparison, the 1i has a bit of a U shaped response where the mids are recessed and the top and bottom are emphasized instead. This gives the 1i a lot of focus in the upper mids and is probably why they have such great emotion, but it also awkwardly takes some of the body away from instruments. Hence the 2e sounding more natural.
The bass is clearly less extended on the 2e. That doesn't mean that it sounds bad in any way, as it's very tight and thick, but it just doesn't vibrate as deep as on the 1i. It's not so weak that it unbalances the sound, but if the fuller mids weren't there to pick up the slack the 2e would be a little top heavy.
*Soundstage:
The 2e stage is notably smaller and less airy than the 1i, sounding much closer and more "in your face." It actually reminds me of the SR series, 225's in particular. The 1i has a lot more distance and width, which gives it a grander sound. This isn't so much a matter of better or worse, but I do feel like the sound has more space to reach out with the 1i while the 2e feels constrained within a set distance.
The separation is clearly better with the 2e, and this is especially apparent with vocal harmonies. Every single voice can be heard at once, and I'm easily hearing many things in general that I never noticed with the 1i after years of listening to them. The separation brings an increase in clarity to the overall sound that makes me feel like I can hear anything with these headphones. Going back to the 1i, a few things get reburied in the mix.
*Random observations:
The 2e sounds a lot more stable and solid than the 1i, which has a slightly more hollow, grainy, almost brittle quality in direct comparison. I don't know if it's the fuller mids or the resonance reductions, but the 2e definitely sounds tighter and heavier in spite of the more limited bass.
The 2e wins by a landslide with electronica. I couldn't really find a single Autechre or Aphex Twin track that I didn't prefer the 2e for. The extra separation, mids, and more stable sound really seem to pay off for music with extreme percussive details like this.
The 1i is still better for classical. The wider soundstage, more delicate mids, and sense of distance suit strings much better. Rock is a toss-up.
RS2e clearly wins in the looks department. The brown headband pushes it over the top, it even matches the color of the new earcups closely. I feel guilty even posting without pics.
Summary:
The 1i still sounds like the higher end headphone. It has the better extension, bigger soundstaging, and classier sound. The 2e is a little closer to the SR series side of things, but the quality gap is not big at all. Despite the $200 difference, I consider them nearly on the same level.
The RS2e should be considered a sidestep from the RS1i, then. It does some things better, some worse. With the RS1e being as lame as it is, it was tempting to think the 2e might offer the upgrade that RS1i owners wanted, and it nearly does. The real tragedy of the RS1e is that it easily would have topped the RS1i if it had just stuck with the RS2e sound and improved it; the 2e's biggest weaknesses are the smaller soundstage and limited bass depth, both of which would have been solved by the larger RS1 earcups and general driver upgrade. Such a waste.
I still don't know which headphones I'm keeping. Again, it's a very close call. I'd be happy to stick with either one of them.
