That would be really cool, but I don't see how that would be possible to combine those two though. The HD800s huge soundstage is attributed to that large cup design. The DD is also another nuance in the presentation. Conversely the stealth is like a smaller damped room, but doesn't sound closed. Stealth has larger soundstage than open back HD6xx. I eq the HD800s to Harman, so both have similar tonality, but different presentation. Different enough to justify owning both as compliments. However I think the stealth is the closest to the one to rule them all. You get the benefits of closed back isolation while also not sounding like a close back, essential no distortion that adds into that incredible "technicalities". I can't image the E3 being more different than similar to the stealth though. I'm sure the difference is extremely nuanced.