Hey Tony and others - good point for me to link to this tread - maybe anyone could give me ideas for my problem.

You're speaking of subwoofers.

As I've prepared my new car for the Mk2 I watched out for what speakers to use. First I took a look at the build-in speakers of my car (New Peugeot 406 limousine). They are terrible quality!! Only plastic-chassis, no two way etc...
The only speakers which sound quite nice are the tweeters in the front of the dash.
So I decided to buy new speakers and I took Magnat with separate tweeters for the back and Macrom with integrated tweeters for the frontdoors and left the original tweeters in the dash.

The sound got a bit better - as good as it can get with a standard tapedeck. :-(

The next thing I did was linking an amp to the system to be able to drive my sub (it's a 30cm (=12" ?) in a tube with bassreflex tube, build it by myself). The amp is really fine and was quite low cost for this quality (about $250).

But now here's my problem:
I had this subwoofer in my old car already. It was no limousine but a hatchback. So there was no problem for the sound of the sub to get through to the passenger's space.
But now in the limousine the sub is not as loud as it was before 'cause the car is much better isolated against noise.
The sub works already very loud and you can feel the vibration of the car but only a small part of the sound comes through.

At this time the sub is lying in the back with the speaker and the bassreflex-opening pointing to the side.
I already thought about decreasing the size of the sub (by cutting a part of it) so that I could make it pointing in the air - directly to the deposit in the back of the passenger's space. But I'm not sure if the sound gets better then.

What else could I do to have a better bass in a limousine (without changing the car too much (to void warranty loss))

Please excuse my bad english. I hope you understood what I mean.
Thanks for any ideas :-)

TeeMcBee