@navyachts I love SVS subs, and I own a pair of the SB-4000, but i have to respectfully disagree with folks recommending the SVS Micro 3000. The specs look appealing, but I’ve had two friends who have owned them and they just don’t go that low, and they will not be sufficient in your room.
The 12” you mention is quite small. Are you sure you can’t afford just a little bit more? What is causing the space limitation? I think the regular SVS SB-3000 would do well, but you the Micro 3000 probably won’t add much more than what the Signature SE can already deliver.