[flyingguy]

What do you think the difference between lyr and vallhalla when pairing with HD600 and 650? Thanks!

 

[Amictus]

  What do you think the difference between lyr and vallhalla when pairing with HD600 and 650? Thanks!

I was asking this question a few weeks ago, and it occurred to me to contact Schiit themselves. I got this reply:
 
Lyr is magic with the Q701s, while Valhalla will struggle. HD650 is a tossup—Valhalla is slightly more open and holographic, but I’d take Lyr’s power and control.
 
If you go with Lyr, get the Tungsram tubes while we have a few left.
 
I went for the Lyr, and have not regretted it. My preferred tubes (among the few that I've tried) for my classical tastes are Siemens E288CCs and E88CCs (FWIW). The synergy with the HD650s is wonderful. Soundstage in all directions and superb revelation of low level detail... I don't own the HD600, however, so can't help there. Good luck!

 

[pdrm360]

For the HD598 , definitely Schiit Asgard.  The Valhalla is an OTL and pairs better with the high impedance headphones.