Craig, there's something I'm missing in all of this. It's my understanding as I add a speaker to a system, SPL goes up by 3dB. So if I have an active that gives me 90dB with a Watt at 3 feet away, if I butt up another active that is eating a Watt, at 3 feet away I'll measure 93dB. If I add another, I'll measure 96dB. Is this not correct?

House of the Rising Sone
Out in the mid or far field
Dedicated mid-woofers are over-rated