No amp for the DT-770 Pro 80? I have to disagree. Even on a Sansa Fuze with LOD to Nuforce Icon Mobile and they barely get enough volume on high gain.
The E7 should have similar results. When I had one I was kind of surprised they didn't get very loud from most portable devices.
Even the 32 ohm Beyer DT-770-990s have never been easy to drive based on my experience with them.
Hmm I may have to take back some of what I said now Tdockweiler. hmm.