I use a pair of DSE 5" bookshelf speakers and mount it on a 28x45cm baffle. Predictably the bass is lacking but I rather have a natural-sounding midrange than closed-sound of boxed speakers.
It doesn't look too bad as well. Some possible next experimentation to fix the bass are:
- dipole subwoofer
- active compensation circuit
I did try using normal subwoofer but it simply ruins the overall sound character.