I currently own the dyaudio 1.3 se and have moved up to a more powerful Amp. this speaker can provide deep enough bass with the right equip. I did have the Sim audio w-3 amp 150w and now have the Musical fidelity 350w amp. big bass difference. I think a sub would ruin the sound unless it was used strictly for home theatre.
another option would be for the price of a sub you could move up to the special 25 which provide more bass and the same great sound as the 1.3se.
another option would be for the price of a sub you could move up to the special 25 which provide more bass and the same great sound as the 1.3se.