There is nothing special about HiFiMan planars. Voltage, current, and resistance operate with them just like they do with every other headphone and speaker in the world.
Powering a headphone (any headphone) with 300W mono blocks is like commuting to work in a Lamborghini. You'll have tremendous pride of ownership, but you won't get to work any faster.
Edited by palmfish - 8/12/12 at 5:26pm