I bought a "Red Wine Audio" modified, all tube input and output, including a remote, external, shielded power supply to replace the original internal power supply, which will support the best DAC chipsets (Burr Brown, included in the chassis) along with the quad AX7 tube output, Dual Mono Wadia, Digital to Analog Converter Chassis. It is like a pre-amp and a DAC in one (well two, since I must also include the external power supply to make it work) unit.
I have been using one of my older computer's hard drive units as a simple digital source for about three years now (a vbery good way to go for the least amount of distortion, assuming the hard drive audio files have never been compressed), along with a homemade external, battery operated DAC or a number of fancy assed sound card, wi-fi, or USB outputs. This unit will take the raw USB buss feed and create analog as close to the source as possible and supply a two volt (heavy line level - six hundred ohm) analog output for my tube amps.
It should arrive on Monday.
I am anxious!!!
Just had a look at their website. Very cool. 
It arrived today, via UPS. It is "running in" right now.
I am taking a short break from the pool to check it, but my excuse was that I needed to check on our rice, beef, muliti-veg, one dish meal, which will be ready in about thirty minutes. That is coming along well, too.
This DAC is awesome! From what I can tell in the two hours I have had it up, I am going to fall in love with digi-music, all over again.
(Where is the "Bull Penis" smilie?)
