I have finally got around to planning the install of my stereo gear from my last car:

- Apline 9855 H/U
- Alpine MRV F545 4 ch amp
- Focal 165 KF splits, still need to buy some rears as well
- Focal 40a 16 inch sub

Only problem is im stuck on how im gonna install the sub, at 16 inches it needs a big box obviously, will go with probably around 75L which is what i had in my last car. But the boot of my TJ is only 17 inches deep under the rods that connect the boot hinges, so it would be a real tight fit to get it in there when u add the thickness of the MDF as well. Will mount the amp in the boot as well and keep everything nice and neat without gettin too complicated. Basically hopin for some different ideas on how to mount the sub in my boot, only real proviso i want to keep access to the spare wheel easy, any help much appreciated

Cheers Tim

We built a 100L ported box for a KJ II GTV to house a 15. 900mm fits between the wheel arches no problems.

Use thicker bits of MDF ( or double them up ) on the longer bits of the box. Add some bracing and you have no flexing at all. My box is over a meter long, has 36mm MDF on the rear and 25mm Perpex on the front.

If you slant the rear of the box to match the rear seat you will gain valuable litres. Also if you can fiberglass round the wheel arches and get every bit of space possible. Basically if your expecting to keep much of your boot, you bought a stupid sub...

We built a 100L ported box for a KJ II GTV to house a 15. 900mm fits between the wheel arches no problems.

Use thicker bits of MDF ( or double them up ) on the longer bits of the box. Add some bracing and you have no flexing at all. My box is over a meter long, has 36mm MDF on the rear and 25mm Perpex on the front.

If you slant the rear of the box to match the rear seat you will gain valuable litres. Also if you can fiberglass round the wheel arches and get every bit of space possible. Basically if your expecting to keep much of your boot, you bought a stupid sub...

Thanks for the advice much appreciated mate, but i doubt i will lose a heap of boot space as im not goona go to 100L, it will be a sealed box max size of around 75 litre could even be smaller going by Focals specs. Going by my old box it was roughly 95cm wide, slanted into the rear seat with a base of 30cm deep, top of 15 cm deep. So should still be able to keep most of my boot space if its roughly that big i think. Can i ask what u used to the line the inside of the sub box as u used perspex on one side, as its something im interested in doing??

Seal the boot from the cabin with two sheet of MDF (one against the back seat, one againstthe parcel shelf and mount it to that Infinite baffle.

Full boot space and some nice clean IB basslines without the peaky ported box with no low end extension.

You don't need to line your box with anything. The only time you would add dacron or filler is if you build the box small intensionsally. The inside of my box is filled with mirrors :bowrofl:

I missed it, are you gunna builid the box sealed or ported?

Interesting idea tim, that would leave a lot of room remaining. Sealing could be a mission, but a 16inch sub is no easy task.

You don't need to line your box with anything. The only time you would add dacron or filler is if you build the box small intensionsally. The inside of my box is filled with mirrors :bowrofl:

I missed it, are you gunna builid the box sealed or ported?

Interesting idea tim, that would leave a lot of room remaining. Sealing could be a mission, but a 16inch sub is no easy task.

lol yeh i actually meant was it lined internally with mirrors, im thinkin i might have it so it faces into the cabin, a sealed box with perspex on the back of it, then mount my amp on one side of the boot and capacitor on the other

My sub box is MDF with carpet inside and a polycarbonate wall on the outside :) It's super.

easy access to the spare wheel...put it in the garage :bowrofl:

but seriously, getting to the spare wheel is a pain with a normal sub. a 16 inch one will be hard. I would think that making a fibreglass enclosursre to go from the towers back to the bask seat. that shoud get you 70 ltrs...will not lots of bracing tho.

be interested to see what you come up with tho :cool:

Seal the boot from the cabin with two sheet of MDF (one against the back seat, one againstthe parcel shelf and mount it to that Infinite baffle.

Full boot space and some nice clean IB basslines without the peaky ported box with no low end extension.


that sounds like a bunch of pigeon english to me.

Basically saying to run the sub as a free air type, giving a 400+L enclosure (of sorts) or whatever the volume of the boot is.

:redface: Wow where you drunk last night?

:redface: Wow where you drunk last night?
I was :badgrin:

I was :badgrin:
yes yes you were

I was :badgrin:

Me too!!! :badgrin: