As Mac said, try using just a pair of L1 Compacts and evaluate the overall sound before thinking about a pair of powered subs.

Additionally, Bose also sells systems for churches, theaters and large halls that is a permanent installation. I don't know the size of your church, but this may be something else to consider. Call Bose and they can provide you with the particulars on these systems.

Good Luck,

Gary
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PSR-S950, TC Helicon Harmony-M, Digitech VR, Samson Q7, Sennheiser E855, Custom Console, and lots of other silly stuff!

K+E=W (Knowledge Plus Experience = Wisdom.)