All components have a sound. Tube DACs were not designed to eliminate the preamp any more than a tube phono pre is. Yes tubes into tubes could get too tubey but if they are well designed they will probably work fine. No generalizations are possible.
Tube DACs
For some time I've assumed that tube DACS are meant for direct output to power amps -- in other words, no reason to use a tube DAC if you are running through a tube preamp (unless all components are by same mfr and designed for synergy).
But lately I have seen posts implying some run Brand A tube DAC through brand B tube preamp -- say, Primal Luna 100 to Rogue RP-9. Can't find any prior threads addressing this topic directly.
So, question: am I wrong to suppose that pairing random tube DAC A with random tube preamp B is a bad, or at least a silly idea, absent a known synergy?
S