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custom subwoofer box in 3rd row seating storage area?

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I'm thinking about doing a custom fiberglass box in the area where the 3rd row seats are supposed to be located. Has anyone done anything similar?

Than you all!

would also love to see any other aftermarket audio builds/mods!
 
I bought this box, from a company in Florida, I will be installing this in the next few weeks. (Waiting on weather to warm up...) You can see from their youtube how it looks, they were great, super fast shipping and its well built.

I attached a few photos of mine, I got the the passenger side one as I wanted it on the factory side. I have one showing the sub installed and the other was my test dry fit. (It will push back further once I remove the plastic trim.)

To me it was worth the money to buy the prefab box, I have built custom boxes for my cars in the past, as well as some of my friends over the years, but I was not comfortable doing a resin box in the trunk of my Tesla. (Big difference between a Honda civic and a Tesla...) My plan is to build a custom shelf in the trunk well to mount the class D amp as well as a switch to turn off the remote turn on line for longer road trips so I don't loose my range. I will also be repainting the grille and removing the polk audio logos, I have had both the sub and grille in different cars over the years and it really shows its age. Have not decided on color yet, I'm between matte black, silver or as close of a blue I can find to match the exterior.

Here is the link to the video of it installed:

Their store: Tesla Model S Subwoofer Enclosure Box | AudioDesigns&CustomGraphics

Brian

IMG_20181225_171331.jpg
IMG_20181220_191129.jpg
 
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I bought this box, from a company in Florida, I will be installing this in the next few weeks. (Waiting on weather to warm up...) You can see from their youtube how it looks, they were great, super fast shipping and its well built.

I attached a few photos of mine, I got the the passenger side one as I wanted it on the factory side. I have one showing the sub installed and the other was my test dry fit. (It will push back further once I remove the plastic trim.)

To me it was worth the money to buy the prefab box, I have built custom boxes for my cars in the past, as well as some of my friends over the years, but I was not comfortable doing a resin box in the trunk of my Tesla. (Big difference between a Honda civic and a Tesla...) My plan is to build a custom shelf in the trunk well to mount the class D amp as well as a switch to turn off the remote turn on line for longer road trips so I don't loose my range.

Here is the link to the video of it installed:

Their store: Tesla Model S Subwoofer Enclosure Box | AudioDesigns&CustomGraphics

Brian

View attachment 372413 View attachment 372416

thats awesome. let us know how it sounds!
i think those are definitely the most common ones. i really wanted to do one in the lower compartment. i have a huge RE sub that id love to put in so i need quite a bit of volume in my box. what volume are your boxes and are they sealed or ported?
 
thats awesome. let us know how it sounds!
i think those are definitely the most common ones. i really wanted to do one in the lower compartment. i have a huge RE sub that id love to put in so i need quite a bit of volume in my box. what volume are your boxes and are they sealed or ported?

I will let you know how it sounds and for sure post pictures of the install. These boxes are sealed, I am guessing they are about .5 - .6 cubic feet. I did see in my searching for box ideas that there were pictures of a custom box made that fit fully in the foot well. I will see if I can find the link.
 
Fortunately fiberglass work is actually pretty simple. Just make sure you cover up the area super well to avoid any drips or spills on to the carpet. I usually lay out at plastic and tape it down, making sure to overlap by a few inches and having tape cover all seams.I then also lay an extra couple of feet of plastic out from the area as well to make sure it's protected.
Make sure to get a decent mold release spray, or a good carnauba wax to coat the plastic to make removing it easier.

If you end up needing even more space than what the footwell gives you, you can always fill the box with polyfill, or something similar and help out for the volume.
 
You can also just use MDF too since its a rectangle cutout, just seal everything really well. You still have to use MDF rings for sub support, as fiberglass alone cant hold the weight of a sub.

I assumed (likely incorrectly) that he'd be using MDF for the top since it would be super simple.
But MDF CAN support a sub, but it'd have to be pretty thick, and would flex quite a bit, definitely not ideal to do just FG for support.

I've actually been contemplating either building a footwell box myself, or building one like the NVX enclosure.
 
Fortunately fiberglass work is actually pretty simple. Just make sure you cover up the area super well to avoid any drips or spills on to the carpet. I usually lay out at plastic and tape it down, making sure to overlap by a few inches and having tape cover all seams.I then also lay an extra couple of feet of plastic out from the area as well to make sure it's protected.
Make sure to get a decent mold release spray, or a good carnauba wax to coat the plastic to make removing it easier.

If you end up needing even more space than what the footwell gives you, you can always fill the box with polyfill, or something similar and help out for the volume.

thanks for the tips! hoping to dive into it soon!
 
I assumed (likely incorrectly) that he'd be using MDF for the top since it would be super simple.
But MDF CAN support a sub, but it'd have to be pretty thick, and would flex quite a bit, definitely not ideal to do just FG for support.

I've actually been contemplating either building a footwell box myself, or building one like the NVX enclosure.

yes i was definitely planning to use a large piece of mdf at the top to close off the bottom mold and to hold the sub. i'm just not sure how i would bond the top piece of mdf to the bottom fiberglass mold? any ideas? lol
 
yes i was definitely planning to use a large piece of mdf at the top to close off the bottom mold and to hold the sub. i'm just not sure how i would bond the top piece of mdf to the bottom fiberglass mold? any ideas? lol

Im pretty sure you do that with the resin and the cloth, possibly using some internal supports like a 1 inch doll rod that adds support in the corners, and maybe one in the middle.
 
On a side note, the weather was nice today and I was able to install the subwoofer and get it tuned. I will say what a difference in the lower end, it brings back whats missing in the sound in my car.

My setup is as follows:
10 Infinity Kappa Perfect (No longer made, I have had it for 10+ years in various cars)
Blaupunkt PA2100 Class T Amp Bridged
Audio Control LC2I

The Amp is small enough to fit under the subwoofer in the side cubby so I do not loose any of the lower space. I also installed a rocker switch from an RV, and mounted underneath to disable the remote turn on for long trips to conserve battery range.

Still need to paint the grille matte black, but it looks and sounds awesome.

IMG_20190203_171152.jpg
 
On a side note, the weather was nice today and I was able to install the subwoofer and get it tuned. I will say what a difference in the lower end, it brings back whats missing in the sound in my car.

My setup is as follows:
10 Infinity Kappa Perfect (No longer made, I have had it for 10+ years in various cars)
Blaupunkt PA2100 Class T Amp Bridged
Audio Control LC2I

The Amp is small enough to fit under the subwoofer in the side cubby so I do not loose any of the lower space. I also installed a rocker switch from an RV, and mounted underneath to disable the remote turn on for long trips to conserve battery range.

Still need to paint the grille matte black, but it looks and sounds awesome.

View attachment 374325
this looks very clean!!
 
Thanks, I am beyond the years of hear me down the block, so I love how it turned out, and no loss of trunk space. I have the executive second row so the seats do not fold down. I will say its like the car was made to have a sub added, there is a grommet on the passenger side thats the perfect size for a sub wire to go through the firewall, and a prefect ground in the trunk right behind the sub.
 
The sub install turned out great. I have been interested in adding a sub as I have for previous cars but I am curious about the current draw on the 12V system. Where is the best place to tap the B+, the battery post? How about the audio signal; where is the best place to connect it?
 
The sub install turned out great. I have been interested in adding a sub as I have for previous cars but I am curious about the current draw on the 12V system. Where is the best place to tap the B+, the battery post? How about the audio signal; where is the best place to connect it?

The 12v for the Amp I took directly off the battery post(safest place), I have a dual motor so the battery is behind the frunk tub and not wedged down behind airbox like on some cars. That being said Tesla batteries are designed for both post mount power cables and the fuse tray being screwed on top. So there was a threaded post on top of the battery terminal that I attached my power lead to.

In regards to line level for audio signal you will need an LC2i, it converts speaker levels down to RCA line level, and gives you a remote turn on for the amp. The speaker wires I tapped were in each door kick panel, I just tapped the right and left front speakers.

As for the switched 12v I used an add a fuse with a 2.5 amp fuse for the LC2i and pulled power from the fuse box in the frunk, I think I used the ABS fuse as its a switched 12v, the risk of overloading the fuse box with the LC2i is minimal.

I got the wiring colors from this guide and where to find the speaker wires, used posi taps to tap the speaker wire.
Sub-woofer and Amplifier Installation | TeslaTap

Please don't do what the above article shows and take a 16ga wire add a fuse to an 8ga wire, that has fire written all over it, use the battery post.