If your not looking for high volumes (as you've said) the Dayton Titanic 10" using the Vance Dickason design... (1.1ft^3 with 100% fibreglass stuffing). Paired with the 250wrms parts express amp (WITH the 6db boost @ 30Hz enabled) should give an accurate response down to around 26Hz. The Titanic 10" is approx US$140, but for $10 more, you can get the 12" version. This seems to work model well in a 3ft^3 enclosure, again, with the active eq enabled. Being a sealed enclosure with Qtc around 0.7, it will have excellant transient response, and have low group delay (giving you the "fast and clean" bass you asked for).
The 250wrms PE amp is around $120 (~$20 more if you want a remote control version).