What a POS! I saw that a few months ago, and about puked! Tubes, my ass. I design professional audio equipment. With the possible exception of musical instrument amplification, the only reason for using tubes for audio products is because people will spend their money for them.
What people "like" in tube gear is NOT accuracy, it's a pleasing coloration. It's a cute massage, but it bears little relation to the sound intended by the producer of your favorite recordings. Honest, I know what they use to record and monitor them in a pro environment.
Of course, that's before you get to the problems you invite by putting a very hot tube inside a computer and genereate some really high voltages to run the noisey beast. Tubes in computer audio are a really stupid engineering choice.
Of course, that's before you get to the fact that, contrary to the statement on their page, Edison did NOT invent the vacuum tube. The tube was based upon Thomas Edison's 1883 discovery in his early lamp of an unexplained electric current that flowed across a gap from the filament to a metal plate. In 1904 an English inventor, John Ambrose Fleming, had shown that this effect could be used as a wireless receiver, two years later Lee deForest added a vital element, a wire grid between the filament and plate that controlled this current flow.