Single vs. Dual Subs

Miller +1on subwoofer isolation.

My subs have been supported on foam padded dollies with extra soft rubber wheels for many years now.
After a move and before a permanent system setup we had our single 18" sub sitting on some folded moving blankets. We noticed how much less the low frequency excited the structure while still providing deep bass.

When we purchased our current 12" subs ten years ago I connected the 12s and the 18" with RS-232 cable and the home theaters 15" Super Nova with L/R interconnects. Effectively creating what's now called a swarm which did indeed eliminate all the rooms bass modes.

We noticed little if any sonic advantage between Cardas Golden Reference XLR to Canare XLR.
On the other hand when I applied the four subwoofers with fourteen parameters of the subwoofers Room Optimization the improvement was stunning while adding the flexibility of remote controlled preset equalization. 

I'm very interested in the "much better solutions available" you mentioned?

@m-db, The much better solution is using digital bass management which includes room control and digital crossovers which are far better than analog crossovers. From less to more expensive you have MiniDSP, DEQX, Anthem and Trinnov. Check them out. If you are a person who is stuck on analog only just forget about it, my mistake. 

I'm running a pair of Tekton 4-10 bass towers & am very pleased. Prior to this, I was using a single REL sub. The bass towers improved not only bass (as expected) but also soundstage width, depth, instrument separation, & top end clarity. A very nice improvement top to bottom. I have these in a dedicated room that is around 15' square.  

@millercarbon Lose the attitude. You’re an a**hole.

@ieales
I am driving the mains as full range because I have no choice.
"What type of XO [BW,LR, BE & order] are you using?"
I would answer your question, but I have no idea what you are talking about. I assume XO is a crossover, but what is everything else?