This will require some thinking, but I'm going to make it work.

I tried to make a ported enclosure for my truck, and blew one of my 10" Sundowns. So, after shipping it back to Sundown, and getting a new one, because I'm sure they won't cover burnt VC's, I forgot to set the subsonic filter on my ported box. So I decided to go a different way.




This is going to be a sealed build, with .75" MDF, with a space in the middle to sink my amp into. It's also going to require some thinking on my part, how to get this to fit behind the seats of my DC. I'm thinking cutouts and fiberglass, and plenty of wood glue and screws. I'm probably going to build the box "in" the truck, piece by piece, carefully measuring and cutting as I go. Also probably countersink the sub in the box, to cover the Xmax of 20mm of the subs. 1500w and 2 12" subs, a beautiful combination.

Right now I'm installing a floor in my house, so it may take a couple weeks to get the build started, that and it's still fricking cold here. Besides, I've got box building techniques to consider. Can it be done, we'll see.

Stay tuned.

 

Not sure you can get anough cubic feet of space for 12" subs with the amp spot in the middle. I ordered a premade box off Ebay for 2 sealed 10" subs and I did not install the amp there because it would make adjusting it a pain in the ass.

Also, I think you will need a shallow mount speaker as my 10" subs could not go deeper than just under 5". Here is my box (amp is under the passenger seat):


You may be able to avoid this building your own box and modifying the the truck (removing the bar that sticks out and the car seat connectors).

Here is a pic to show the bar:

 

I test fit the woofer before purchase. The magnet will clear even with building around the brace, and I plan on countersinking the amp about .75". What my main concern is, is will I get the depth I need? I'm thinking about a cutout on the back of the box, and fiberglassing the hole. I'm actually planning on building the box IN the truck, to maximize my space, and if I have to, stuff the box a little, to get the 1cu.ft. that's recommended for each sub. Im still in the box design phase though, as I plan to add a more powerful amp to my front speakers, and need a place for the distro boxes to go. When I start, I plan to take many pics, and post them up, to give everyone the hope that 12's can be had, with a little effort.

I've had 6" subs before, 2 JL Audio 10w3v3's, in a premade box from Supercrewsounds. What they did is cut a hole in the back of the box, and cover it with .25" MDF. I'm thinking fiberglass, because these subs will see 1500w on a Sundown SAZ-1500D. The amp is 14" long, so I plan to mount it vertically, and use spacers on the locking hook for the seatback, to push it forward a little. That should give me space for the amp. I'm just deciding if I want to go with just the positive distro block, I have the Sundown grounded all the way back to the battery, or go with pos. and neg. on the back wall.

 

If you plan on building the box into the truck, might I suggest placing the two subs side by side for shared airspace; placing the amp off to one side. Also, I would recommend using the rear wall of your truck as your rear enclosure wall. This will allow for more air space and will help anchor your box to the vehicle, which can result in seemingly tighter bass. This will require some precise cutting for your side walls, secure fastening, and a thorough sealant (I used silicon and Dynamat).

You should consider perforating or removing the seat-back plastic panel to allow for more sound to pass through the seat itself. This makes a pretty big difference. If you want to perforate it, drill several holes or come up with your own method. After, you can cover the modified panel with upholstery to keep it looking good back there.

If you can build it right, I can assure you that it will not disappoint. We built an enclosure like the one I've described into a double cab with two JL 10" W1 woofers and you wouldn't believe how great it sounded.

 

With 1500 watts, I'm assuming that you're running 1/0ga wire. In any case, I would ground the amp to the closest possible solid grounding point near your amp. I don't believe there is any reason to run a grounding wire all the way to your battery.

 

Not to question your purpose too much, since I like someone who works to innovate, but with the box/size consessions you'll need to make to fit 12s, won't you basically get the same level and range from a properly fitted set of 10s?

 

Grounded to the chassis, I was seeing voltage drops of 2-3 volts. Grounded to the battery, I'm seeing voltage drops of .2-.3 volts. Wasn't much of a pain to get it run, and it seems worth it now. Yes it's 1/0 wire.

Hopefully not. With two Sundown SD-2 10's, I was getting around 122db's in .6cu.ft. enclosures. This will be a 1.9 cu.ft. enclosure, stuffed a little to try and make it 2-2.2 cu.ft. I hope to hit 130's with this setup.

 

2-3 volt drops?? that's insane. I would seriously question other factors that could contribute to this. I am running 2350 solid watts with all of my amps grounded to the chassis and I have never seen drops even close to this, even before I upgraded my electrical system. None of the high end systems that came out of our stereo shops ever had the need to ground an amp directly to the battery.

I would anticipate this setup to be close to 140db if executed properly. I was able to get 135db out of a single 10" alpine type R with my first bass setup.

 

I'm looking forward to this. Have you thought about using fiberglass as your rear wall? The sides, front, top, and bottom can still be MDF. You may gain a 1/2" of clearance.

What kind of subs are those? I haven't seen that logo before.

 

You can fit 12's in DC's no problem. Alpine Type-R 12, 1.60ft of airpsace. Port tuned at 35hz.

 

I've thought about fiberglass, but hate sanding it. As for the subs, they're Shok Industries Triton 12's. What I'll probably end up doing is cutting a hole in the back of the box for the magnets, and glass those. No sanding involved.

 

These aren't shallow mounts though. They are 6 1/8" deep. That's why I'm building the box in the truck. To maximize space for these things. I'm also considering an amp swap, to an Alpine PDX-M12. The space savings will be considerable.

 

The Alpine PDX amps are decent, but I would wager that the sundown is much better.

Also, this is a rough draft of the enclosure I described in my previous post. If you use something like dynamat over your rear wall, cut the sides as closely as possible to the contours of the rear wall, secure the enclosure tightly with L brackets, and apply a liberal amount of silicon to ensure a full seal, this will yield more air space. No fiberglass required.


Not drawn to scale...

 

Thanks. It's definitely an option that I should consider. I know the sundown is probably the better amp, but it's all about space at this point. So, I'm looking to scale down as much as possible. With the Alpine, I can hide it under the drivers seat, not have to cut out an amp rack in the box, and gain extra airspace. It's so hard to decide what to do. My mind is racing with possibilities.

Good news is, we finished installing the flooring this weekend, and all I have to do is baseboards and finish trim today. So, I made a deal with my wife that I get next weekend to work on the box. Stay tuned for updates, they will start soon.

 

I am very interested in this as well, cannot wait to see what you have cooking. i am a big sundown fan, had a pair of SA12's on a SAZ1500d in my 07 access cab, looking to use my SD amps in my 2012 DC

 

6.5" subs may be a little too deep. I'm hoping to get away with not having to cut out and glass a hole in the back of the box, but I'm going to have to countersink the sub in the box, just to clear the 20mm Xmax of this sub. Because I'm building the box so close to the rear seats, I don't want the sub hitting the seat and distorting. I'm using .75" thick MDF, so even if I have to cut a hole, it's no big thing. I have to get some resin to seal the box up anyways, so some matte will be no big thing. At least I won't have to sand it, if I do end up cutting a hole in the back of the box.

 

shaneckc has some really solid advice he's providing here...cutting a hole out of the rear of the enclosure and fiberglassing it is going to compromise the structural integrity of the rear of the enclosure anyway so integrating and structurally strengthening the rear wall of the cab and integrating it into your enclosure is very likely going to yield the best strength to airspace ratio possible for your application. The power and air being moved in your setup is not to be taken lightly -

You're going down a good path - and I'm never one to say something can't be done...would just be a shame to see you invest so much time and effort and not extract the maximum amount of performance out of your set up. Good luck and keep us updated

 

Also, the small amount of flexing that the rear wall does in applications like the one I've described can result in some minor aperiodic dampening, giving you a small amount of gain at lower frequencies.

 

Oh man. Now I don't know what to do. I already have the back wall deadened. Getting the tightest possible fit is fairly easy to do, cutting and using the back wall as part of the enclosure. Or do I go with making a whole box, and fiberglass a 6x6" cutout in the back of it. So many decisions to make. I know what shaneckc is recommending WILL get me the required depth, and silicone is cheap. Or make the box removable, have those fiberglass holes cut in it. I do hate fiberglass.....................hmmmm.

 

You will not have to cut the back wall to do what I am suggesting. The only advantage of going with the cut holes in the back of a complete enclosure would be being able to remove it. Personally, when I do the stereo in my future double cab, I will be building it to the rear wall.

And yes, fiberglass sucks