In terms of sound good Class D amps I have heard and good tube amp setups I have heard differ not just in components used end to end but soundwise as well. Tube amps often provide some degree of warmth through the midrange. Class D amps I have heard deliver more of a "liquid" midrange but not warm at all. You have to add that somewhere else if warmth is what you seek. A good matching tube pre-amp does nicely.
I have one mostly digital (with phono and line level analog inputs plus various digital) integrated amp (Bel Canto C5i) and my main rig with BC CLass D amps and ARC tube pre-amp. They are both excellent performers but have their sonic differences, mainly the touch of warmth the ARC preamp delivers. I can listen to either happily for hours.
I have one mostly digital (with phono and line level analog inputs plus various digital) integrated amp (Bel Canto C5i) and my main rig with BC CLass D amps and ARC tube pre-amp. They are both excellent performers but have their sonic differences, mainly the touch of warmth the ARC preamp delivers. I can listen to either happily for hours.