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?

mijostyn, I appreciate your suggestions and yes I'm pathetically stuck on analog but our low frequency system is master and slave digitally processor controlled.

At shows I'm regularly impressed by total bandwidth room correction demonstrations and then I walk into an analog demo and am often quickly reminded. 

divertiti, after many 18" single subwoofers when some dedicated subwoofer manufactures began designing ten and twelve inch top line models I liked the idea of at least two smaller units. After experimenting with four subs I found my room loaded nicely with just two 12"s running summed L/R located asymmetrically in the rooms largest bass modes. Good luck with it.