I have a 2003 trailblazer lt, not ext, and I was thinking about runnning 2 18 xcons. Not a lot of people are running 18s in trailblazers because of the limited room in there. Crazycricket12 on smd forum gave me dimensions of his box. It's 21h x 45w x 30d. He's using the torres box calculator. The box has a square port in the middle of the box facing back hatch. The dimensions for the port is 10h x 10w x 12L. It says port area is 100 ft2 with tuning at 32.75hz. The total net volume only excluding bracing is 12.41ft3.

Would this work??

That's a very very small port and a small box for 2 18"s.

I would do 1 18" in the proper box, it will be louder.

That's kind of what I thought. Sooo maybe 1 18 is what I should go with then? How about an 18" Zcon? I've been drooling over those haha I have a Crescendo Bc2k so that should pretty much match up perfect!

The Zcon is a great choice, I highly recommend them. What are your goals for this setup? Any electrical upgrades planned or performed already? Do you have a budget in mind?

My goal is to have a louder setup with a better low end. I have a 15" hdc3 and its jus not hitting the lows like I want and is not as loud. I have the big 3 done in 0ga and a deka 9a31 in the back. For a budget, are you asking for the sub? Maybe around 650.

Are you looking to add more power or electrical, or just looking for a subwoofer upgrade?

For now just adding a subwoofer. Later down the toad I probably will add more power and electrical.

In that case, I would pick up something like a Zcon 18 or a pair of nice 15s. Icons come to mind.

I'm thinking about the zcon 18 then. What do they stack up against, output wise?

It's kinda hard to answer that question as there are always variables. They are certainly capable of extreme output. I can tell you some of the drivers that I was thinking about purchasing for the dual 18 build I'm working on now. I considered Fi BTL N2, Ascendant Audio Mayhem, SSA Zcon, DD 9518SC, Ascendant Audio SMD and the Incriminator Audio Warden. I almost immediately scratched the Warden and SMD options due to cost and decided against the DDs because I wanted something a bit out of the ordinary and I live down the road from DD HQ. The last 3 all had similar power handling and were all very appealing to me. I really wanted to try the Zcon and it was a good bit cheaper than the other 2 so I ended up with a pair of Zcons.

I hope that wasn't too ridiculous, it's late and I'm barely hanging on.

Ohh no that wasn't ridiculous at all, I think you just sold me on the zcon! Haha