First, I apologize if this isn't the right area to post this question. If so, please tell me and I will delete it.
I have had a headroom total bithead for quite some time now and I've always thought that it worked well enough. More recently, I purchased beyerdynamic dt770 pro 80s and monster turbine pro coppers and I'm looking for something a little better. The bithead seems to have a lot of noticeable hiss regardless of the source i'm using it with. And beyond that, I'm not even sure I can hear any difference between the built in DACs in most of my devices (samsung galaxy nexus, google nexus 7 which is supposed to have awful audio) these days or my laptop's sound card and the bithead.
I don't need anything super-portable but transportable is what I'd like. I want to be able to use the amp/dac through USB audio out on my Nexus 7 when i'm lounging or with my laptop at a desk. Right now, I sometimes drag the bithead to work but like I said, I have my doubts if its really worth it.
I listen to bassy electronic music most of the time (dubstep, IDM, UK garage, etc). I am more concerned with amping the beyerdynamics but something that also helped the turbine IEMs would be nice. The only other thing I've looked at is the Fiio E17 but I'm not sure if its a step up
I'm hoping to spend less than 200 bucks. Any help or links are much appreciated. Thanks