Five is magic for me too. Mine weren't near the placement problem yours were but then my room is more like 17x24x9, and its not just the room its the listening position as well. Everything in my room is spooky good dialed in for the sweet spot.
Had one Talon Roc sub for years. Replaced that with four 10" subs and 2 Dayton sub amps. Was going to sell the Roc but just for kicks put it back in for a test and its not going anywhere!
If you experiment I think you will find stereo/mono makes no difference. If you find any stereo bass let us know, nobody has, I sure haven't. That's not to say the bass doesn't sound and localize as if it was stereo. It certainly does! In spades! But every bit as good mono as stereo. Tried it both ways.
I would never subject my precious stereo signal to DSP or any EQ. But if you can EQ one or more subs separately without polluting your stereo signal then with 5 subs and enough time and energy you should be able to get near ruler flat response down to as low as you want to go.
DBA Rules!
Had one Talon Roc sub for years. Replaced that with four 10" subs and 2 Dayton sub amps. Was going to sell the Roc but just for kicks put it back in for a test and its not going anywhere!
If you experiment I think you will find stereo/mono makes no difference. If you find any stereo bass let us know, nobody has, I sure haven't. That's not to say the bass doesn't sound and localize as if it was stereo. It certainly does! In spades! But every bit as good mono as stereo. Tried it both ways.
I would never subject my precious stereo signal to DSP or any EQ. But if you can EQ one or more subs separately without polluting your stereo signal then with 5 subs and enough time and energy you should be able to get near ruler flat response down to as low as you want to go.
DBA Rules!