I am currently researching the upgrade of my Concert stereo and am looking for some ideas, suggestions, feedback, web site URLs.. you getta the picture eh?
Also, I want to keep the factory deck/CD changer and use the pre-outs on the deck.

The area that is giving me the most problems is what Sub-woofer config. to go with; 2 x 8" or 1 x 10" and where to mount them. I really like the "SteathBox" but its too expensive. I have also considered copying its design. (2 x 8").
Also, what about putting a single 10" in the back left corner of the trunk?

This is going to be a complete DIY project where time, not $$ is no object. I would also like info on where to mount amp(s), what aftermarket speakers have been used in the doors and rear deck.

thanx in advance

Dear Krator.
I dunno wheather you´d rather do a stereo-freak version of that subwoofer-setup you´re contemplating, or if a more down-to-earth version would do it for you.
If the latter is OK with you, I would strongly recommend that you check out Blaupunkt´s CMS 265 all-in-one 100W sub-box.
They call it the landmine. Probably because of the shape, cause it not the meanest sub on the market in terms of pump. It does add a very nice depth to the sound though, and installing it will take you about 1 hour. It comes with a built-in amplifier and the shape and size (like a flat oversize shoebox) lets it fit nicely on ex. the back of either of the rear seats. The 99-model gives you 100W, compared with the earlier models and their 60W. Plus the price has gone down on the new model! All in all a very good deal, I think.
I just mounted one in my A4 Q Avant...but I´m not 100% sure if you can get that particular model in the US...? Otherwise drop me a mail, if I can help further.
A last note on placing subs and amp´s i the car:
It´s very straight forward, so maybe you´ve already thought of it: Use the spare tyre-bay.
Simply get rid of that 5th wheel and build a box (wood or alloy) to support the trunk floor and provide nice-looking and practical room for all the hardware.
That´s about it. I hope that vcan help you with your project!
All the best. Lasse Bauer, Copenhagen, Denmark.

The install was extremely easy - battery and remote turn on from front, grab preout signals from driver's side rear speaker, ground amp, and VOILA!!! The amp ran 100W X 1. The sub is in a sealed box, with the front surface angled to match the rake of the back seats. It's got some pieces of hard-side velcro stapled on the bottom so it doesn't move.

This setup cost me $550 CANADIAN (pretty cheap for clean power and a decent sub), including the fabrication of the box. I installed it myself however.

The setup proved to be highly upgradeable too (as it was designed to be); I now use the PC 225 to run my highs (4 X 25w at two ohms to stock rears and MB Quart component set up front) and run a PC 275 to the sub (1 X 150W). Nakamichi in dash 6 disc changer has replaced the Concert head.

You can check out my car in the registry.

Cheers,
Mark
99.5 1.8TQMS APR'ed