Originally Posted by jmh

Well it all depends on your needs and how much you want it to be concealed.
One example of a hidden subwoofer install using a 10" JL Audio sub is below



The sub won't be too expensive and depending on how perfect you want the
box to be it could be build for very reasonable money.

I always like retaining the stock look of a car and not to attract too much attention to it from the outside.
The amp could easily be mounted underneath the cargo cover.

- Jan