Confused about your price range since you mentioned the MU2 ($18K) but then you said $5K.
Re: DACs, I liked the Mearson DAC1 Mk2 quite a bit for its smooth musicality but liked my Mojo Audio Mystique X SE better, and also liked the Mojo better than the Tambaqui. Still have the Mojo DAC but also an Aries Cerat Helene, which I like even better. However, at that level, the incremental improvements seem to get smaller. I would still like to hear:
- Plaback Designs Dream DAC
- Grimm MU2
- Totaldac D-1 Bi-Unity
- Meitner MA3i
- EMM Labs DA2 V2
- Aries Cerat Kassandra
Some of those have an integrated preamp, but may still be above your price range. If your price is around $5K, consider a Mojo Audio Y DAC.
The one that blew me away recently, given the price, was an old Monarchy 22B with BB PCM-63 DAC chips, for which I paid $350. Tonally in line with the naturally organic sounding Mojo Audio and Aries Cerat DACs along some of the best bass I have heard from a DAC. A bit less refined than the Mojo and AC DACs but, otherwise, very listenable. I am considering having it upgraded.