One thing to be aware of is that the sub will not add clarity to the main speakers unless the sub or the preamp provides a high pass filter to them, blocking out the bass that is now to be handled by the sub. Otherwise you're just adding murk to the low end.
Also, if your room is small, chances are you don't need a subwoofer at all. The addition of one will muddy up the sound and probably activate room nodes that will devastate the imaging and sound balance of your speakers.
Also, if your room is small, chances are you don't need a subwoofer at all. The addition of one will muddy up the sound and probably activate room nodes that will devastate the imaging and sound balance of your speakers.