A lot of people are running the HD800s on neutral upstream systems with great results. The HD800s are exceptionally detailed, and while not perfectly smooth, they don't have an emphasis as such on the treble. On a neutral system well extended accross the range they have strong bottom, excellent mids and treble, without any emphasis.
With the LCD-3s if I tune my system to be slightly on the bright side of things they are still clearly warm sounding. I don't at all mind it, but I would never call them neutral, no matter what you do.
Edited by negura - 5/26/13 at 6:18pm