There are a few types of Subwoofers to choose from.
Regular sub-woofers are just that a Sub, you will still require a box for it. There are many things that can be done with. You can purchase a pre-made sub box. The other option would to have a custom box built. In a lot of cases this is actually better the box can be made to fit the car specifically and by the specs required to have the Sub perform its best.
The next option is Pre-loaded Subwoofers. They are an amazing option, the Vendors use their knowledge to select the size and volume of the enclosure that will enable the Sub woofer to operate its peak level. With this in mind, they do the technical work behind the scenes to make sure you get the best sounding system. The end result is precise calculation, calibration, and perfect tuning.
Another option which is great for saving space is a powered Sub. They are a great option for Convenience, as well! Light compact and they have the Sub woofer and the Amplified in one nice package together. It can also be a much easier Instillation. In a lot of cases they are easily hidden beneath the passenger seat and add a nice boost of low tones to your sound.
Come in and let us help you find the Solution that is right for you.