The JL audio 12W7 and the 12W6v2 are the best products. They are not only loud but produce amazing clarity and can hit all notes HIGH to LOWSS. The technology put into them blow all other products out of the water. Unlike most subs a less powerful amp is needed to use these subs which is good because you wont have to purchase a expensive amp and shows how crazy they design these machines to work superbly with less power than other companies. Plus they aren't just loud and sloppy like most subs, they are loud, clean, and can land any note of bass. If your willing to pay than the best choice would be the 12W7 then the 12W6v2. Pleasure is a guarantee when choosing either of these.
L-7's
kicker
kicker L7 or fosgate t1
The Kicker 1500 Watt subwoofer is very, loud, but doesn't have the best clarity and can get muddy. Consider Pioneer subs.
For the money the L5 is the best sub by far. Then it would be the CVR series.
One can purchase a Kicker subwoofer at many electronics retail stores such as Best Buy, Future Shop and Visions Electronic. One can also buy them at online shopping sites.
Kicker is a much better quality subwoofer than Pyle, and it will have much better bass as well.
The Kicker ZX300.1 Subwoofer Car Amplifier is great.
The Kicker CVR subwoofer comes in sizes such as 10", 12" and 15". You can purchase these subwoofers online from the official Kicker website online store.
i have always ran jl audio and kicker products and have never had any problems out of either...i have 4 15'' kicker cvr's in my escalade at the moment with 2 kicker 1000.1's running them and they are very loud...the sound quality of the jl is a lot better though and if you go with jl your going to spend more money
http://www.kicker.com/content/Contact_US
The Kicker enclosed 12 in. subwoofer can always be connected to your factory radio, and it should be very easy to do.
It's a dead subwoofer.