Just curiously - is there an ee lurking in the thread who can explain the difference between the headphone out and preamp outputs in these units? I'm wondering how hard it would be to take a well regarded diy amp like the krell ksa5 klone, dynalo mk2, or even something like the wire, and add a preamp output.
Edit to add, as an aside, that if anyone has been waiting on a bottlehead sale to bite at a mainline - there's a site wide 10% off starting this evening/through tomorrow ( http://bottlehead.com/smf/index.php/topic,5878.msg56710.html#new ). If you are willing to pick up a soldering iron and want a highly resolved, uncolored parafeed tube amp that mates perfectly with hd800's, has excellent timbre, effortless transients, tight impactful bass and extended, but never strident, trebles, now's your chance.