View Full Version : Custom Subwoofer Replacement

08-09-2007, 01:55 AM
Ok, it's 12:33 am, I've been at this for a while now. There were no :beer: involved as I got high on fiberglass resin :lmao: Matter of fact I think I dont need a nose hair trimmer. Well here are the pics. This is a build that I am doing for Sno Bored, we will TRY to put it into his rig before the rally saturday so everyone can see/hear it.

Materials used so far: Fleece, cat hair, fiberglass resin, mekp (catalyst hardner), 3/4" MDF, nails, wood glue, DAP caulk.

The first is the picture of the orignal sub in my 93'. I took it out to primarily get rid of it and take measurements to make the new encolsure.

In the second pic, you can see the mounting for the sub. The sub is removed via 3 x 10mm screws.

Third pic shows the amplifier and the harness disconnected.

Forth, you can see the box starting to come together with all the angles to accomodate for the notches in the vehicle as well as wiring and piping.

Fifth, you can see the space that is empty, well not for long, that space will be used to house the amplifier, so everything is out of sight and won't be in the way of anything at all.

08-09-2007, 02:02 AM
6. Literally it's a very thin box. VERY thin.

7. There is the notch I made so the box sits in recessed so the panel can go on without problems. You can also see how close I am cutting the subwoofer opening so that we can get the biggest size in the enclosure without sacrificing space.

8. Getting it ready for fleece so that fiberglass can be laid.

9. Fleece on and stapled so that when it hardens it doesn't retreat from edges and it's easier to work with when stapled down

10. Cut the excess off and now, really really ready to get fiberglass.

08-09-2007, 02:09 AM
11. Mixing Pepsi. :D Resin and hardner are being mixed and WOW it smells :boozer:

12. There it is, the stuff that I used to kill brain cells.

13. There is the front view. I am using pieces of MDF to make sure the fleece doesn't settle inwards. Because if it settles inwards, that means there will be less space for the woofer or the woofer may not fit. However if it settles outwards then the box may not fit into the truck and that would be really bad. So I put little pieces in there just to make sure it settles just right.

14. There is the backview of the fiberglass hardening.

When I get back from work tomorrow I'll finish up the install and post some pics up with the sub loaded and the amp rack. So wish me luck.


08-09-2007, 02:19 AM
Very nice Q!

Get that done to show off at the rally and you may be able to pick up some orders :)

After you're done fixing up the 80's you can borrow my LX to come up with something cool for that :thumb: :D

08-09-2007, 02:25 AM
No problem, I will be happy to help you with the LX ;)

08-09-2007, 07:53 AM
um, no porting?

08-09-2007, 08:41 AM
Any plans of making some extra before I go to a shop and have them do it?

08-09-2007, 09:02 AM
I think you're going to have a winning product on your hands! Will the plastic panel still go back on when you're done?

08-09-2007, 09:53 AM
WHat volume are you getting in that box? There are a few subs on the market that can run on just .5 cubic feet. An Alpine 10 for instance. It looks like you could kick the box forward to gain a little bit more volume.

Green Machine, you wouldn't want to port a box this small. Sealed is the way to go for good tight bass.

Nice looking box!


08-09-2007, 10:07 AM
Definitely need an Audio section at the rally. I'd love to have a professional ear look at my stereo and amp settings....

08-09-2007, 11:19 AM
I have been dragging all morning. By the time I got done cleaning up and finally getting to bed it was 3:30. It is running approx .75 ft^3.

I wanted to go sealed for this application. The reason being that if we did a port, it would be a nightmare to get the port volume right and still keep it behind the panel and frankly it would not be worth it because I am not charging much for these. However port would be louder but sloppier (some people have different opinions; this is mine).

Ok, here is the really cool thing that I like about this box compared to others I have done in the past. I don't know if anyone noticed but this box is made for a 12" woofer. Previously I have done some 10" because the length behind the panel is only 4.5" (tapers to 3.5") plus add all the other stuff and you are in a bind. I am using a truck series subwoofer which is a 12" and only 2.5" deep. If TreerootCO reads this, he can see what I was referring to for his 2500. I'll have some more pics for you when I get back home, and finish this up. I'll take some of the sub that is being used for this vs. other subs and you guys can see the difference and then it will all make sense.

As far as spacing the box out, it's not going to happen. Our initial concern was to make sure everything looks stock, and believe me I don't even have 1/10" to spare behind the panel. The other way to space it out was to shave down the panel because the panel has cross bracing in the back which can be take out using a dremel. But for the amount of space you would gain .1^3 ft would not be worth it.

Daniel, I'll help you out with yours at the rally.

Stay tuned, I will post the amp rack pics and the rest of the pics tonight.


08-09-2007, 12:51 PM
Definitely need an Audio section at the rally. I'd love to have a professional ear look at my stereo and amp settings....

I could look this over for you too. I love this stuff, and put myself through school tuning and building systems.

Smurf blue cruiser, topless... the cruiser that is. :lmao:

sno bored
08-09-2007, 01:32 PM
Q This is looking great. I can't wait to hear how it sounds.

08-09-2007, 06:19 PM
Daniel, I'll help you out with yours at the rally.Q

Cool! Any particular music to bring?

The CD's I typically keep in my truck are all MP3's recorded at 192k bitrate. 7-8 albums per disc saves space and I'm told only an audiophile could hear the difference versus a native CD format and then only if I had a great system (mine is decent but nothing ridiculous).

08-09-2007, 07:17 PM
Nothing in particular. My suggestion to you is bring something that you like (really really like). That way you know what it's suppose to sound like and you can tell what difference it has made when it's properly tuned. So, bring a cd or genre of music that you like and we can tune it accordingly.


08-11-2007, 04:30 AM

Sorry for the delay in posting up the pics last night but here it is. I finished the basic design last time, but the only thing left to do this time around was another coat of fiberglass resin and it was done. The problem with doing second coat is that you can't mix it hot because it will crack or worse, when the subwoofer is playing in a sealed box, it will make the fiberglass shatter (seen it happen) :eek: So you have to mix it very light, because it will flex if there is a lot of bass and hold up to beating easily. Another thing I did was rolled around the box so the entire inside including the MDF gets coated in resin and provides the box rigidity. Ok enough with the talking here are the pics.

1. This is the sub I am using, a pioneer premier sub. (has a little wood dust on it). Very shallow sub (if anyone wants comparitive pics with other subs, let me know).

2. As you can tell, this box was designed with this sub in mind, because frankly nothing else will fit, at least not a 12" :D and who wants 8" woofers anyway?

3. This is what it'll look like when the box is loaded.

4. Box profile.

5. Getting high on resin again

08-11-2007, 04:34 AM
Ok, since I mentioned that I mixed it light, it has taken a LONG time to harden. But the results are excellent.

6. Here is the resin poured in and you can see the side of the wood which is also coated.

7. Wired the sub, there is the amp that is going to be used to run the thing.

8. You can see the resin is still glossy, and FYI it is completely dry, that's how you know you have a good coat.

It's 3:35 right now and I need to make another one for acon40.


08-11-2007, 05:32 AM
Success at last !!!!!

It fits behind the panel. I feel like Rocky right now and want to go run around and the neighborhood with my fists in the air, but the neighbors might call the cops.

Well I check the sub excursion and it doesn't hit anything or touch anything on the panel so we are good. To check excursion simply use your battery to pop the sub out (for a millisecond) and visually check if anything is touching or rubbing.

OK OK, here are the pics.

1. Since this is a sealed box, it has to be airtight for the sub to make pressure inside and do it's thing. So when making a hole for the wire to go through, you have to make sure that after the wire goes through, that hole is also tightly sealed.

2. In this pic you can see where I tied the knot that way the wire doesn't slide at if someone pulls at it as well as it forces the caulk (white thing at the end of the wire) to go inside the drilled hole and sit inside next to wire and seal up the rest. You can use terminal rings but 9/10 times they leak and I HATE using those.

3. Here is a comparison pic of a normal 12" sub. You can see there is no way that was going to fit in the allotted space.

4. Also the design is completely different where the MTX is bowed in the middle and the premier is completely flat with ridges (increases surface area to move air)

5. There is the excursion testing apparatus :lmao:

08-11-2007, 05:47 AM
Here are some more pictures

6. The panel in place and snapped in.

7. Same as above, different angle.

8. The products that were used, and also an 8 gauge wiring kit for the amplifier.

When sno bored gets to Denver I can put everything in his truck and you guys can see the finished product and hopefully hear it (if I am not passed out by then).


sno bored
08-11-2007, 10:06 PM
Q installed the sub and amp at the rally today, and it sounds great. The sub/box and the amp all fit behind the rear panel, and it looks stock. Q is a great guy and I have to thank him for helping me and the rest of the club with audio stuff.

Shark Bait
08-11-2007, 10:47 PM
Looks great. Mind me asking what all this cost? :D

08-12-2007, 10:36 AM
Fun to hang out with Q and Sno Bored at the rally yesterday and play with stereos. A few tweaks to the settings on my sub amp made big difference. :) The new rear infinty speakers are great. As I was driving to the Outback Steakhouse post-rally dinner last night I kept thinking my phone was ringing because of the newly audible highs on the John Mayer CD I was listening to! :thumb:

Next step, at Q's suggesting, will be to disable the rear roof and dash speakers to remove the "noise" they add and see what difference that makes. Also to time-correct the imaging.

His trained ear can hear things I could not, but overalll the difference is noticeable.

Thanks Q! :cheers:

08-12-2007, 12:18 PM
Next step, at Q's suggesting, will be to disable the rear roof and dash speakers to remove the "noise" they add and see what difference that makes. Also to time-correct the imaging.

Thanks Q! :cheers:

This is good advice, lots of folks don't understand how to set up a sweet spot with audio imaging in a vehicle, most people get it when it comes to home theater, but there car can sound like the music is coming from the center of the dash if everything is timed correctly.

Can't wait to hear it someday.