So, when you use them via bluetooth the internal amps power the drivers, but when you connect via the wired option it uses the amp in your device? That seems a bit wasteful, why not just have a converter to take the amplified signal from your device into a line-level signal and send it to the internal amps?
I'm surprised that there are't more internally-amplified wired headphones like what Blue is doing, you could pair the amps for the drivers to get the best results and do away with the need for stand-alone headphone amps that reduce portability and add expense.
HT: Sony 940C, Oppo 203, Harman/Kardon DPR1001, Infinity Interlude IL40 x2, Infinity Interlude IL36C, Infinity MS-1 ii x2, Infinity MSW-1
Computer: Elac Uni-Fi UB5 x2, Elac Element EA101EQ integrated amp, SVS SB-12NSD
Dedicated 2-channel: Infinity Intermezzo 4.1t towers, Bluesound Node 2, Emotiva PT-100, Crown XLS 1502, Furman PL-8C