Found this forum in search of information on a pair of subs my uncle gave me from a storage unit he bought. In a google search the only place that had any information on what I was looking for was this forum so here's the story. My uncle bought a storage unit and it had a bunch of brand new car audio in it, most of which he sold bigger named stuff like MTX and Polk. The stuff he couldn't sell (3 items) he gave to me. Two are 8 inch Petras subwoofers and one was a set of Polk 2 way tweeters I believe they are modle 2100's if I remember correctly. Now the Polk tweeters I plan on using my self but the Petras subs I opened and took them out of they're original boxes and put in a ported box, they are dual voice coil and I've never hooked up dual voice coils but have owned some JL dual voice coils. I watched a 15 minute video on you tube and hooked them up in the ported box, they bumped but not well at all and it's possible they aren't made for the ported box or I hooked them up wrong, I did notice they sounded much better when I put my hands over the port holes so maybe a sealed box is what they need? Any way sense I spent $50 on the box I put them in and I couldn't get $50 worth of bump out of them I figured I'd try my luck with them on craigslist. $25 was my highest offer so I turned to google which led me here. I figured any sub with dual voice coil is good not that I have a whole lot of knowledge of this world I do know the Xplodes I've owned in the past (being single voice coil) take 1000 watts of power to bump close to the JL dual voice coil powered by a 300 watt Alpine amp. So I guess to just get to the point I'd apreciate any info on these Petras subwoofers and I'd like to offer them for sale here if worth it, can any one help me with this? Also this is the first forum I've ever joined so please be patient with me as I'm just figureing out how to use it, thank you.