I have a pair of decent Niles OS20 speakers on our open covered patio. The patio roof is an extension of the main house roof, so there is a couple of feet of "attic" space up there, and I've been thinking about adding a passive free-air subwoofer in the ceiling to augment the Niles.
Getting line-level to this location is not practical, so I'm thinking about wiring it in series with the Niles.
Does anyone make a decent ceiling-mount outdoor-safe 4 ohm sub?
I could use an 8 ohm but I don't see the point in wasting the power on resistance with it being in series with the other speakers. (I've even thought of going with some cheap 4 ohm car audio subs, the patio ceiling is always dry and out of the sun and relatively non-outdoorsy, but I figured I'd check here first for recommendations or ideas.)