Highroller - wht not call Schiit and see if they have a suggestion to match better to your liking with the cans you have.
Also I found this post on headfi if you haven't seen it
"Favorite tubes for my Lyr / PS Audio D-Link3 with following headphones:
HE-500 - Amperex Bugle Boys, D-getter, '58-'59
Mullard CV-2492/3, '60s
Also, again if you haven't seen it here is the headfi search on all Lyr threads there http://www.head-fi.org/newsearch?search=schiit+lyr
Also I found this post on headfi if you haven't seen it
"Favorite tubes for my Lyr / PS Audio D-Link3 with following headphones:
HE-500 - Amperex Bugle Boys, D-getter, '58-'59
Mullard CV-2492/3, '60s
Also, again if you haven't seen it here is the headfi search on all Lyr threads there http://www.head-fi.org/newsearch?search=schiit+lyr