Officially, and unofficially, Ultrasone does not recommend any particular amps for its headphones.
I can truly understand that many here would like to hear what Ultrasone recommends. However, as it has been stated many times throughout this forum, a persons ears, and their respective setups, are individual and unique to that particular persons' tastes.
Listening with headphones is a very unique and personal experience. It is a hobby that a person follows to achieve their own form of perfection that fits their own personal preferences, music tastes, budget, surroundings, etc. One particular amp may go well in a setup with a particlar hedphone, however, he same amp and headphone in a differnt setup may have completely different results.
It would not be fare for any one particular manufacturer to make objective and opinionated reccomendations based on their own listening habits.
Each person is unique, and that's exactly the way we all want to be. Otherwise we'd all be robots listening to the same style of music, through the same setups.
