If the rest of the speakers are working then you have the amp for the 4 door/rear speakers. You can check, that amp is in the trunk on the driver side mounted to the tire well floor under the black stirafoam insert.

The Bose sub amp should be mounted right in the inside of that hole, toward the center, see the picture that Paul350Z posted "Stock Amp" If you dont see that amp unit in that area were the stock sub goes, then it is missing too.

You can hook up an aftermarket amp and sub, but for most aftermarket subs you will need a box enclosure. There are free air subs but not to many of those and you are limited on choice.

Your best way to go is replace the missing stock stuff, since you dont feel like doing much modifications.

 

I have a stock bose sub along with the mounting bracket I can sell you. Send me a PM if interested.

 

Any suggestions on free air subs?

 

kicker

 

So Kicker otherwise need a sealed box and the box should have XX volume depending on the requirement of the sub in question, right? I'm just starting to try to understand this stuff ... what happens if there is too much volume (or too little) ?

 

Kicker has subs that has the free air witch does not use a box. And yes the box volume should match the subs requirments. If it is to big or to small it will affect the sound (HZ range) when building the box it should be close to the req. of the subs.

 

Sealed Enclosure must sound better then ... otherwise why go through the trouble of building a box ... ?

 

OOhh ya it is much much much better if the sub is in a box