[mister skinner]

I'm in the market for a new amp for my HD600s and don't know which one to go with. I can't seem to find any in depth discussions on how either amp pair with the 600s. I don't mind spending the extra money on the Valhalla if its a better kind of sound. I'm leaning towards the valhalla because of the tubes adding a little more warmth to the 600s (which they could use just a little).
 
any input?

 

[punks15]

I've never listed to Valhalla but Asgard by itself is a smooth and tend toward the warm side IMO. It'll pair nicely with the Senns
Also consider Graham Slee Novo for a cleaner and more tubey sounding than Asgard