Which is better for outdoor speakers, acoustic suspension or bass reflex?

In a nutshell acoustic suspension speakers don't have a port (hole) in the cabinet and bass reflex speakers do. The port allows for a deeper bass response than the speaker would normally be able to produce, though not necessarily more accurate.  This said it explains why many if not most outdoor speakers are of the bass reflex variety. The port helps deliver more bass which is important in an outdoor environment.

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