Audio Systems: subwoofer, cd player pioneer, bazooka tubes

Question
I would like to add a subwoofer to my car audio system and need advice on how to proceed.Car currently has Pioneer 3800  CD player,Pioneer 6200F 4 channel Amplifier,and four Pioneer A1781R speakers.Was considering Bazooka subwoofer for convenience and less loss of trunk space.Not interested in ultimate bass(classic rocker),so question is-powered or non-powered tube,4ohm or 8ohm,single or dual coil,or something totally different?Appreciate your help,thanks in advance.----------------JSW  

Answer
I absolutely hate the sound of the bazooka tubes. the reason they are small is because they are tuned higher than they should be (for my taste at least).  also if you're a (classic rocker) you'd probably rather have the sound of a sealed box instead of a ported one,  the bazooka tubes are ported so they're out on that count as well.
You'd probably be very happy with one of these:

http://www.cardomain.com/item/POLDB124

cheap and effective and able to go into very small sealed boxes.  if you're going to build your own box then you can save some cash there or if you want to get a prefab box you can use this one:

http://www.cardomain.com/item/RTE31512

of you have more space I think the sub would sound a little deeper in this box:

http://www.cardomain.com/item/RTE31612

a good amp to run this sub would be this one:

http://www.cardomain.com/item/POWOV2800

let me know what you think.