will reversing polarity on sub damage it?

No it hasnt blown yet.. I havnt really taken apart the tube yet.  And I Havnt had a time to check the ohms, but that is a good idea and will do just that with my multimeter next time.  

I doubt I would blow it though, if my friend is right (I dont know if he knows what he's talking about on this one), he says this is a 4 ohm SVC subwoofer.. and I have only had it attached to one of my channels.. so it is only putting out like 125 watts x 1 @ 4 ohms stereo,  and that is if the ohms is 4..

I think there is a possibility, this subwoofer might be a SVC 8 ohms, or might have a damaged voice coil that reads much higher above 5..  As well, there is also a chance that this subwoofer is a DVC 4 ohm subwoofer.. in which case it might have been wired improperly by the person who originaly used it, and that it might have been wired in series with an 8 ohm load..

I will test it out when I get the chance to, and post my findings regarding the subwoofer.

Thanks for the reply guys..  I figured it out.. It wasnt my expectations, the subwoofer really is way too quiete for what it should be putting out.  I had just put a multimeter to the sub, and got a 13 OHM READING !!!   LOL.  I have never had a subwoofer before with such a messed up voice coil... and i've handled a lot of subwoofers.   haha, my eyes almost poped out of my eye socket when I saw the reading.. 13 ohms, wow.. pretty high.  I will be returning this subwoofer to my friend who gave it to me, and claimed to have been pounding it without a problem before he gave it to me. 

It has nothing to do with ME overloading it, I only ran one channel of my amplifier to the subwoofer, and the subwoofer was suppose to be rated at 4 ohms.. so that's about 125 watts RMS power, so it's not my fault...  Actualyl, if anything, it was about 13 ohms when he gave it to me.. so I am really curious what kind fo power I was putting out?   Anybody got any idea?  If I can put out 250 watts RMS @ 2 ohms, and 125 watts RMS @ 4 ohms.. how much would i be putting out at a 13 ohm load??  My guess would be about 35 rms, what do you guys think?