FiiO E1 Portable Headphone Amplifier with Y-Cable (Black) - Reviews
Pros: Remote Functions. Rubbery Cable. SQ increase.
Cons: Ergonomics, especially clip. SQ increase is small. Some of SQ increase could be LOD effect alone.
This is not intended to be a full review. This was an impulse buy. I followed a link to a web retailer and noticed they had the black E1, so I jumped at the low price. What the heck, I said. I have previously purchased a Fiio E3, which I used for a couple of months and grew tired of.  I've been trying my new Fiio E1 out on my IEM mainstays: TF10, HF5, and RE0. I like it on each, although the most noticeable increase in SQ is with RE0.  The bass is so much better. There is nice rubbery texture, without boominess, meaning its not fast, but very present and very enjoyable.
It is now important to note that my source is a 4th gen ipod nano. Now I have read that the bass is pretty bad on the nano's hp out and one of my reason's for getting the Fiio E1 was testing this theory. Perhaps I should have just got an LOD for my cmoyBB. This would be a much better test, right? Probably, but I've also been impressed by the comments of in the slight increase in clarity using the E1. The cmoyBB smooths out the high end, which I often find annoying. So I was definitely looking for something new.  Generally speaking, there is an increase in clarity as well, although I notice it more on the TF10 than on the RE0. I'm still left wondering if my enjoyment of the E1's bass is as much due to LOD effect as it is the amp circuit.  No matter, really, for $20, any enjoyment is enough.
I would like to try the E1 with my Rockboxed gen5.5 ipod classic.  Right now, I can't get output in Rockbox and using native firmware I get static.  I had bought the classic refurbished, so it could be a dock port problem. However, I have used the classic, in Rockbox,  in a speaker dock I have and it worked fine.  I will need to reformat the ipod and try it some more.  I have read that others could not get it to work with Rockbox, so we will see.
Despite a somewhat stiff cable, I like the feel of it and it seems sturdy. I agree with others who say its too long. On the other hand, the remote would not be very useful if it were very close to the ipod.  I've been wrappring my IEM cable below the Y split and leaving the E1 cable at full length.  The clip is annoying in that it is hard to use without pressing the buttons on the remote, but because I've been wrapping my earphone cable, I don't find the clip useful anyways. I may find it useful when I am walking around with the nano and E1 in my pocket.  As yet I have not needed it.
All in all, I like the E1.  It will be a while before I decide if it will become a permanent part of my portable set up, but for now I am enjoying it.