I own a Wadia 861. For a while I ran the 861 direct to the
amps with very interesting results. The sound was clear and detailed without being too cold. Adding a King Cobra to the Wadia will smooth things out quite a bit. I eventually could not resist buying the vk50se. Overall I prefer the preamp in the chain. But it is sometimes still fun to run it direct for the best in separation and tranparency.