Originally Posted by Pianist
Great review ClieOS, except that from reading it, I got the impression that RE252 is not really better than RE0 - just different. Yet you say that RE252 deserves to be crowned as Hifiman's new top of the line IEM. Can you explain a bit more why you prefer RE252 over RE0 overall and what makes RE252 a better all arounder?
BTW, RE0 with bi-flanges has a somewhat V-shaped response. If you try it with stock single flanges or UE single flanges, it becomes a lot more neutral. I found say that with single flanges, RE0 doesn't have much character of its own, except that it's just slightly on the warm/dark side.
When I rated RE0 a year ago, I give it a really high prise for its neutrality, transparency and extension. It was marked down on its requirement of an amp to reach the best performance. When I am rated RE252, I find it to be great at mid while retaining most of the neutrality, transparency and extension of RE0 (but not 100% of). The good news is of course RE252 doesn't need an amp to shine. So in a way RE252 traded off some of RE0's edges to address some of its weaknesses. I see this as a positive move overall, but it is not an large step forward IMO. However, from my own brief audition of a few 'new' top-end IEM (UM3X, W3 and IE8) a few months ago, I come to a personal conclusion (as unreliable as a brief audition can be) that, despites all the 'technical' achievement in universal IEM's world over the last year (true three ways and such), I didn't hear any major improvement in the sound. Sure there are small improvement here and there, but I didn't not sense that we have reached the next level yet. You can say I am finding the same conclusion on RE252 - not that it doesn't have improvement of its own, but as many other IEM of this caliber, it has done its best trying to push through that invisible wall (of sonic performance), but the closer it gets, the more difficult and smaller each step becomes.
I pick the big-bi-flange mainly because of better soundstage (which correspond to the more V-shaped like freq. resp.), but it does loss some of its warmness. However, since I am using my RE0 with T4 (a warm amp on its own) most of the time, I felt they compliment (or compensate, depend on how you like to read it) each other well.
On a side note, some of you might find it strange that I rated Fisher Audio Eterna highly while the feedback of others seems to be very much mixed. The reason is Eterna isn't the kind of IEM aims to maximize sonic performance, but aims to please. To me, it is like blending all the wrong ingredients to create the best gourmet dish. The end result is pure joy in my ears, and that's the only thing that counts.