One of my friends has a Lampizator 5 and it's a very good sounding tube DAC. I don't think it is as quiet as DirectStream or nearly as finely nuanced. But that being said, I only heard the Lampizator in his system compared to the DirectStream in mine.
Of course from what I know about tubes (and I do have a fair amount of tube gear that I really enjoy) they add more noise and distortion than solid-state so some fine detail seems to always go missing. The strength of tubes as I see it is in providing a smooth musical presentation and the better tube pieces don't lose that much detail... but compared to the near-state-of-the-art DirectStream they seem to lose a fair amount of musical nuances. And the big plus for DirectStream is that although its topology is solid-state it provides a very non-fatiguing, musical performance... akin to tubes, but without losing the fine details.
Of course from what I know about tubes (and I do have a fair amount of tube gear that I really enjoy) they add more noise and distortion than solid-state so some fine detail seems to always go missing. The strength of tubes as I see it is in providing a smooth musical presentation and the better tube pieces don't lose that much detail... but compared to the near-state-of-the-art DirectStream they seem to lose a fair amount of musical nuances. And the big plus for DirectStream is that although its topology is solid-state it provides a very non-fatiguing, musical performance... akin to tubes, but without losing the fine details.