I don't want to sound rude, but this comment really makes it seem like you haven't done your research. The mini-XLR connectors on an Audez'e LCD-2 earcup are simply there because it was an easy standard connector to adopt which allows for simple cable replacement, not because they "require" balanced amplification. Sennheiser doesthe exact same thing on the HD650, only with a proprietary connector. I don't want to speak for everyone here, but I personally believe that the LCD-2's can compete with any headphone in their price range, even with a relatively inexpensive amplifier.
That's why I love them, they're incredibly easy to drive without sacrificing quality.