More power does not help in the bass department if the amp can deliver as much or more power than the headphone is rated for. The same can be said for headroom. For most people, they listen to popular or contemprary music which is limited or compressed (not mp3 data compression), so the need for large amounts of headroom are not there. In the case of such compressed music, should one listen at volumes so large as to push an Asgard 2 or Magni to their limits would most likely result in hearing damage. Surely something that none of us want. Not many headphones have the power demands of an HE-6 so gobs of power are not usually needed. Even if you're listening to classical music or acoustic jazz there's enough noise and incidental sound that affects the DR and that listening at a reasonably loud level should still fall within the power of such amps.
So rather than just shoot my mouth off, let's go through the numbers. An example is the HE-500 a headphone with more than average power demands.
1W will deliver 119 dB SPL, extremely loud and would lead to hearing damage if one is exposed to excessively.
90 dB SPL requires only 1.26 mW
Few people listen at 90dB SPL average.
If one is listening at 85 db SPL, they will need 39.8 mW
It is unlikely that one will need the 44 dB of headroom which would require 1W peak power.. The Asgard 2 can deliver 1W of continuous power, the Magni slightly more at 1.2W.
Edited by StanD - 6/19/14 at 3:03pm