Personally I prefer a DAC's fixed output if it has any type of attenuators. Even better is no variable output at all. My DAC is the excellent sounding LAB 12 DAC 1 Reference. Sure it has no features to speak of other than input selection and has a fixed analog output using a pair of 6922, but it sounds phenomenal .
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