The E11 is known to be popular with Beyer's. don't own them so i can give you some thread hunting help
http://www.head-fi.org/t/584101/review-beyerdynamic-dt990-premium-32-ohm-and-fiio-e11-and-e7
"FiiO E11
This thing is about as straight forward as it gets. Charge it, hook up the LOD cable to the iPod, plug in the phones and twist the knob. With the DT990's hooked up to the iPod, the first thing that hits me is VOLUME. This little bugger can drive these headphones to face shattering levels, and I'm half-deaf. With these headphones on bass-heavy songs, the highest I can drive the headphones is at volume level around 4.5 before bass-distortion starts rearing its head. Its no fault of the amp. Everything comes across very clear from the highest freqs all the way down to the bone thumping bass. Turning the volume down to try out the bass boost, it works as advertised, providing more body to lower frequencies in songs with less of a bass line. Lets face it though, if you're using the bass boost, you're probably listening to some version of techno, electronica, or dubstep. These tracks shine with the bass boost. Level 1 gives a bit more body and thump to the music, and generally sounds more like I imagine it should sound, without losing anyting else in the music. Level 2 takes that and just goes nuts. Bass will over power some of the mid frequencies, but good lord. If you're a bass-head, make sure you have something a little higher on the Ohm levels. I can't drive these headphones to where I can hear much BUT bass at level 2.
Now for the puzzling part of this little gadget. The Gain switch. I started to write this review with it set to "L" or low. Everything was coming across a little, well, weak, requiring me to turn up the volume more than I was really comfortable with. Upon switching to "H" though, everything starts coming through. The music is, I don't know how to put this, "fuller". Details come out in the music. I don't know if it is the sensitivity of these cans, but the High gain setting really sounds better.
As far as build quality, I don't have any complaints. It is very light, so its easily portable strapped to the back of my iPod with some good battery life for as small as the battery is. No word yet on actual life time of the battery, as I forgot to time it. I was in audio nirvana and I forgot. The cover for the battery does feel a bit thin, and you really have to press on it to get it to snap back in to place if you ever have to take it off. You shouldn't really need to though, so that's just a nitpick.
My biggest issue is the volume control knob. In and of itself, it is great. Volume is smooth to pick up, the knob has a good feel to it. My problem with it comes from the fact that input and output are right next to the thing. This is an issue because when its all hooked up, the volume knob is right next to the jumble of connectors, making it a slight challenge to adjust while walking. Had the knob been on the side or opposite end of the unit, I'd have no issue. As it is though, it is the most glaring fault of the unit.
On to the scores:
Amplification: 10/10 - For 32 ohm phones, it can put out WAY more power than you can deal with.
Clarity: 10/10 - No hissing, distortion or any other modification of the sound besides amplitude.
Ease of Use: 8/10 - Can't charge and listen at the same time. Knob is hard to use when hooked up to source and cans.
Build Quality: 9/10 - Feels solid, wish the battery panel was a bit thicker, wish it was a bit heavier.
Overall Value: 9/10 - Cheap, easy, good amplification. As good as it gets for the price."
http://www.head-fi.org/t/588321/beyerdynamic-dt990-premium-help
So yes. the E11. is probably what you want. purple angel up there agrees so i should be in good shape.
haha
