I'm using a single small REL t5si sub with my Harbeth P3esr speakers. I moved it around the floor until I got a good sound. Running the speakers full range and I keep the crossover on the sub set fairly low. The sub volume is also very low. It's a subtle difference, but the arrangement creates a bit more body in the bass. The speakers are actually fine without the sub.
I use a different system for Home Theater, with a noisier subwoofer.
I use a different system for Home Theater, with a noisier subwoofer.