When I bought my G Coupe I was suprised at the lack of bass. I had a 12" Cerwin Vega sub that I had saved from 2 cars and 2 moves ago. I built a new box for it and bought an Audiobahn 8000T 400W RMS mono amp (on clearance) to power it. The amp was located in the center of the spare tire (It fit perfectly in there.) I used a Soundgate LOC to tap the rear wires coming from the HU to the B(l)ose amp. The sub box was a simple ported cube. One of the requirements for the box was that it would not be permamently affixed in the trunk. I needed it to be easily removed if I need room for suitcases, etc.

The good: Sounded great.
The bad: Box took up too much space and looked very plain. Amp was located in a place where there is no air circulation at all, which would be very bad when the temps hit 120 during the Vegas summer.

So I decided to build another box for the sub. I wanted something that would fit underneath the rear deck (where the 6x9s are.) The trouble was that to have a great sounding box, I needed to have to have the correct amount of air space in the box for the sub to work. The depth and diameter of the 12" speaker and the amount of free air space needed inside the cabinet would not allow me to build a box that would perform correctly AND fit in the narrow space under the deck. So that led to another plan...smaller speakers.

I'm not trying to win any SPL contests. I just want subs that can sound deep and clean up to the max volume of the Bose. So I decided that if I found decent high excursion 8" subs, I would be in business. But of course, the price would have to be right. I found some 8" high excursion Audiobahn on clearance (once again) that met the frequency, space, and power handling requirements I had in mind. Not that I am a big Audiobahn fan. There are tons of better brands out there, but by the simple fact that I am not going to replace the HU, you can tell that "decent" is good enough for me.

Anyway, here are some pics of the box I built. The amp is mounted on the side so it can "breathe" better. The lamp power and speaker leads are connected to the box via quick connect plugs so I can have the box removed from the car in about 30 seconds if need be.

Sounds great and looks good. I could have done better job on the fit and finish of the inside of the box, but this was a learning experience. I have never built a box wher the INSIDE of the box had to look as good as the outside. The next one will be better!

 

You're one of the "realest" dudes here on G35...you're not an installer but managed to tweak out an incredible looking box...you're very humble about your install. I think it looks awesome (a hell of a lot better looking than my 2 10" subs sitting in a box in the middle of my trunk!) I have to admit now that I've read your post I will be starting a new project...build my own custom sub box! Thanks for that post man

 

Wow...Brian, the box looks great. Good job man....I wish I had skills like you.

 

that looks sweet.How much did this run u??

 

That is hot man..

 

VERY VERY NICE! I'm not an audiobahn fan myself, but nevertheless, your install looks fantastic.

I would have thought, by looking at the pics, that you have built many boxes like this before. Very professional work. Kudos to you!

 

Thanks for the kind comments. I though you guys might like it and be inspired to come up with some even cooler designs.

G35audioman, like I said, Audiobahn's quality (and sales tactics) are subject and I'd never use it for competition use. But for my little project, it'll do. It's not like I'm using Jensen or sumpin' Hahaha!

The subs were $69 a piece. MDF, PVC, Liquid Nails, wiring, etc. came to maybe $50. Not bad, huh? I guess I'm the kinda guy that can't stand paying someone alot of money to do something that I can do myself. I've built bass cabinets before...but for my bass rig when I played in a band a few years ago. The thing that you have to remember is that you have got to plan everything out very carefully when you make a sub box. It isn't as easy to build a great sounding box as you might think. A poorly designed box will make a terrific speaker sound like crap, where as a well designed box can make an average speaker sound good. Speaker/cabinet design is actually a very scentific endeavor and it really helps to have good software to help you get the most out of the speaker, box, and amp. People that have heard the box can't believe that it's only a pair of 8" subs in the trunk.

The best part is that it looks like it is permanently mounted, but can removed in 30 seconds for extra trunk space. I'll take pics of it going in and out of the trunk once I get my G back next week.

 

That box looks good enough that I'd like to ask you how much to make me one? I'll look for your next pics to come!

 

one question.. why are your subs facing the side of the car? I belive that if you face them towards the trunk you will get much better deeper sounding bass. Also the seat comes down so if you really want to do damage face them towards the cabin and drop the seat face ports inside too man!!!... instant itchying and heart throbbing bass ! lol i dont even have a g35 but i build all my boxes myself too had 2x 12 T1 rockford F. 1000 rms amps 1 for each sub and it was crrrraaazyyy...SPL felt like im cruizing 60mph with windows down lol even when parked. anyhow thats a great looking box major probs on the carpeting and design its a nice thing you sealed them off inside they perform cleaner that way! GJ!

 

If you want more punch, you should put the ports pointing in the direction of the cabin, which is exactly what I did. In a ported box, the bass resonance comes from the ports...all of the air moved by the subs comes through them, tuned at the frequency that I chose, which is 40 Hz, with an F3 of 35Hz. In the case of a sealed enclosure, you might want to point the subs at the cabin, but in my case the direction of the subs was inconsequential. Plus the length of the ports needed in each sub chamber required me to mount them in a front-to-back orientation rather than side to side.

As for making the cabinet for sale, I'm not sure yet. I would have to have enough interest to warrant the planning needed to mass produce the box. It took me about 12 hours total to make it over about a week. I could probably get the time down if I made several at a time. I don't know how much car audio shops would charge for somethin like this. Hmmmm....

 

for a custom box like that around 300 - 900 dollars easy depending on fit/style and quality. also the subs "if" they where facing cabin would produce the extra SPL. Not all the sound comes through the ports the cone does some of that work. Still a nice install.

 

I might be in for one if yo want to make one for my JL 10's pm me and let me know if you want the bussiness

 

That's nice... a simple and clean design is always nice... main thing is that the sound comes out perfect right...