Has anyone else done this? I want to upgrade my audio system in my grand prix and want to reduce the footprint of the system as much as possible. I have a Tahoe so I don't realy need the trunk passthrough, but has anyone done this with a GP? thinking passthrough ported?

I've seen it done before, not sure if it was an 8" or 10" sub, though. I'm sure someone has a pic.

I've seen this one here:
http://www.grandprix.net/upgrades/audio.html

but was hoping someone had one that was more... idk...

That's not the one I was talking about. There is a guy who has one where the sub IS the passthru.

I made one but the sound sucked, no resonance in the cabin I guess, just the design of the car. I still want to try it again with a different box and another 2 12" subs facing the back. And I used a 12" it was a tight fit.

yea, I was looking for a single sub, 10 or 12... just a little bass.

There are subwoofers that are free air subs that are design for what you are trying to do. Instead if making a sealed enclosure, the sub will use the trunk itself as an enclosure. Hpwever, I think you would be happier with a with a nice set if mid and highs with a 100 watt x 4 @4ohm amp or 100watts to the front and 75 watts to the rear. A nice set of 6x9's with power will be a dramatic upgrade for you bass.

That would be MEEEEEEEEEEE!

I used Sub box calculator to design my box to be as thin as possible. The box is about 5" on top, 9" on the bottom and 15" wide IIRC. It is angled to fit tight against the back seat. Even though the board goes all the way across my trunk. I have the amp mounted on the board.

How did you secure it to the back seat? do you just have the one amp for the sub? how much power? how does it sound?

It is heavy enough, and tight across the width that it does not move. It is a 300 watt MTX 10" and a Profile 200 watt amp from Crutchfield. It has enough power to shake my trunk lid (big time) and make my mirrors vibrate enough they are useless, but I don't listen to it loud. We are a family of musicians. I like me hearing, it sounds great IMO, mostly because I made the box with the exact volume MTX recommeded for this speaker.

http://www.crutchfield.com/p_489AP400/Profile-AP400.html?tp=115

http://www.crutchfield.com/App/Product/Item/Main.aspx?g=520&i=236T4510&tp=111

I found this earlier today :
Ebay custom GP Sub Enclosure

It looks fantastic in that it is cut to fit in nice and tight. however some questions for those of you who have car audio in their GP

Would it not be better to have forward facing subs?
Would one 10" sound fine instead of a pair?

I know it has alot to do with taste... but I want people's thoughts.

You can get a full custom box for that price. http://www.woodlawncabinetry.com



It's usually better to face the sub to the rear. 1 10" will be fine, adding a second only gains you a few dB of loudness.

Why Come?

General consensus is you tend to get less cancellation from sound wave interference with the subs facing the rear. Here's crutchfield's take: http://www.crutchfield.com/S-gv0JUYadEYD/tech/kb138.html

The biggest thing to keep in mind is that you should match your box volume to what the manufacturer recommends, unless you know what you're doing. Thats why a full-custom box will be superior to a pre-made. They're also similarly expensive, if you're not building it yourself.

ahhhhhhhh, excelent information. I have learned alot today! Thank you!