I have a Polk Momo 12" DVC sub in my boat connected to a 1 ohm stable amp mono amp. It has worked fine for several trips and suddenly stopped working last weekend. I havent had a chance to pull the sub to look at it yet since it is behind the drivers kick panel. I did meter the speaker leads at the amp and it is showing 2 ohms (which it should since it is a DVC sub wired in series). The amp appears to still be working - all the lights are still working on it, no fuses blown. Any suggestions? What voltage range should the amp be giving me on the bridged speaker outputs? Do you think the sub could be blown?

Voice coil could be blown?

Correction...subs voice coils are wired in parallel giving the 2 ohm load.

I know several people that have blown that sub by delivering just slightly greater than rated rms power to it.

what amp and head unit are using ?

Amp is kenwood 9103D and HU is the Surpa stock Kenwood MP400MR

Kevin- hopefully it just came unplugged. Sometimes all that bass breaks the wire where it plugs into the sub.

Kevin, If your fluke meter is showing around 2 ohms then Your sub is fine, which also rules out any wiring to the sub. If your speaker wires are correctly connected to the amp, then your problem is in the amp. The easiest way to test would be to just connect a speaker outside of the boat. Or you could remove the amp and take it to a shop to bench test. Some times you can actually smell the amp and if it has a burnt oder it is fried, this doesn't always hold true though.