IF we all put our heads together I'm sure we can design a Valve output DAC for easy assembly by those who are interested. DAC kits are available at reasonable prices on the internet:
http://shop2.hifidiy.net/index.php?m...dex&cPath=8_12 or here:
http://stores.ebay.co.uk/gigawork-sh...=p4634.c0.m322 and a valve output stage could be sourced here:
http://www.diyhifisupply.com/node/399 or here:
http://cgi.ebay.com/DAC-TDA1543-NOS-...item33614264fd or even here:
http://cgi.ebay.com/great-USB-valve-...item2a0a1e5e56
Chassis are available here (for example)
http://shop2.hifidiy.net/index.php?m...index&cPath=18 and here:
http://stores.ebay.com/davids-HIFI-S...=p4634.c0.m322
So all the various elements are available to construct a DAC with valve output to feed into a WAD/WD amp (or in fact any other amp)
DAC kits exist with multiple inputs, co-ax/ fibre optic and USB so it should be easy to satisfy any request.