2 B1's vs 1 B2

Does 2 B1's = 1 B2 as far as the load and low end presence and projection?

I have:

L1 Model I w/2 B1s

L1 Model II w/1 B1

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Using the Model I or II for 1 acoustic guitar and vocal (If there is a difference above)

Model I or II w/1 B1 (Small acoustic room)

Model I or II w/2 B1's (Outdoor patio venue)

Model I or II w/1 B2 (Small wedding when also have to DJ)

Model II w/1 B2 and Model I w/2 B1's (Large wedding when also have to DJ)

Comments on usage?

Note:  I use a Fishman Loudbox Mini to plug in my Acoustic Guitar and vocals for mix and effects.  Use the combined output with effects directly into the L1s.