Adding Sub to current system

Just happen to think of a trick for placement. Place the sub where you sit, and play the system. Walk around the perimeter of the room and listen. When you find a spot that has the best sound, that's where the sub goes.

To touch on the question of what your missing is questionable.
I can live with a well imaging speaker that rolls off at 40hz.
But you're missing about 10% of the music. If that much.
Good 40hz bass is MUCH better that bloated anything lower.
Sub's are very hard to blend perfectly with satalite speakers.
Once you've had full range speakers and then go the Satalite + sub, there's definatly a differance.
Just my two cents worth. John

I have a Rel B3 with my Dynaudio C1's and getting the phasing right is the tricky part. I have mine crossed over at 32hz (C1 rated to 45hz) and the gain up and there is no BOOM here. Honestly I will say if the phasing is off and or crossed over too high it will have a boom. I get that last '10%' but it really adds to the mids and overall sound stage.

Look into either a 215 or larger VMPS sub. They are totally adjustable to your room/system and can be bought with amp, with outboard amp, or without amp. I have the 215/with VSS upgraded driver and the bass blends with very quick speakers so that you have NO idea there is a sub in the room except the box. The dynamics and sound quality are unmatched at anywhere near the price. You could get one with an amp new for under 700.00 delivered to your door for the 215 or under 900.00 delivered for the larger. You can make the sound rounder, if prefered, or tight and punchy, or anywhere between. Just plain awesome sub.

Sounds like some expertise is required in implementing a sub with smaller monitor speakers. The Sonus Faber speakers sound very good and I don't want to mess it up. One procedure was mentioned on this thread, yet I wonder if there is a standard approach to connecting the sub, there is also the cost of IC's to the sub if it's at a distance. My current location idea is about two meters from my system, however I wonder about vibration, maybe if the sub I choose accepts speaker wire connect from my amp connected right to the speaker outputs??
Thanks,
Rpg