Maybe try to get HD650's headphone cable, it's much cheaper then other "upgrade" headphone cable.
Also HD650's cable is much better the HD600's, that's a cheap way to go.
If you can find Oehlbach's, not too much expensive...
There will comes a new headamp from Singlepower, I'm waiting for some feedback from Mikhail.
But my answer will be the PPX3-6SN7 or the new one.
Thanks all of you!!!
I think there will be a big hole on my...