Eddie Current Black Widow 2- $1500 This is one of the best solid state amps around for any price bar none. It has an insane amount of power and can drive any headphone period. This is what I used with my HE6 which is the hardest headphone to drive that I have ever used. It can drive Susvara, HE6, Tungsten, 1266, Utopia and some stupid stuff. Their is a channel imbalance on the 1/4 in adapter until you jiggle the 1/4 for the correct insert depth. Power cycling also fixes the issues. Takes time to get used to, but it's the best amp I have ever used.