A4 Boot Custom Sub Enclosure

Caesium

My BM is fixed!
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I started building a custom sub enclosure today in the boot of my A4
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Site of Enclosure with trim removed
08032007166.jpg

Front cover before fitting
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Front cover fitted
08032007169.jpg

Sub and trim fitted

Only 1 problem, is that I didn't build an enclosed structure, there was very little bass, I now need to build a rear section for the box to enclose the sub, which should be interesting due to the odd shape of the space.
 
very neat how was it easy to remove the trim in the car?
is that the sub amp above the rear arch?

good luck with the enclosed structure.

:rockwoot:
 
Its dead easy to remove the trim, the amp on the wheelarch is the BOSE one for all the speakers.
 
wow... great work... my project b6 sline is in the process of an ice install.... want to do it myself. i have just done head unit with a stunning silver sony but the rear speakers dont work... any ideas???? also is there any adaptor for cd auto changer that is in my glove box or the computer display???

have you stuck with audi head unit????
 
you need an adapter to hook the rear amp up to the Sony HU
Sell the changer as it won't work with an aftermarket HU
No you won't get DIS, only Blaupunkt and a few others offer DIS compatibility and the lead is about £60, so totally not worth it.
 
Chris, you'd be better off using the other side as there's far more room and you can fit a square enclosure behind the trim, though you do need to cut the back off the cubbyhole. You can then fit the amp on the drivers side. This is my attempt which works really well in my B6 Avant, but I really must get round to finishing it off and make it look a bit tidy-er.
AvantSubinstalled.jpg

AvantSubinstalledtrim.jpg

AvantAmp4ch.jpg
 
Jeez wow Andy what amp is that model make
does this feed all the speakers inc the sub?
 
That amp looks like its powering 1 set of speakers and one circuit bridged for the sub
 
AndyMac said:
Chris, you'd be better off using the other side as there's far more room and you can fit a square enclosure behind the trim, though you do need to cut the back off the cubbyhole. You can then fit the amp on the drivers side. This is my attempt which works really well in my B6 Avant, but I really must get round to finishing it off and make it look a bit tidy-er.

Only problem there is I have already cut the rear off of the cubby hole!
Any idea how much a new piece of trim would be?
I assume the N/S is bigger because of the lack of fuel filler.
 
Blimey you did a really neat job, I assumed you'd just left the door off, as you get a door on both sides in the Avant.
It's much bigger, at least on the Avant, about twice the volume with no tricky curves to negotiate.
The amp is an old school Alpine V12 F400 (£80 off ebay), powering the sub and the front Alpine components.
 
AndyMac said:
Blimey you did a really neat job, I assumed you'd just left the door off, as you get a door on both sides in the Avant.
It's much bigger, at least on the Avant, about twice the volume with no tricky curves to negotiate.
The amp is an old school Alpine V12 F400 (£80 off ebay), powering the sub and the front Alpine components.

No door on the saloon i'm afraid just a cubby. Damn that saloon!
 
with ease if you know how :whistle2:

fibreglass resin
fibreglass matt
fibrglass hardener
pieces of corematt
plenty of rolls of masking tape
roll of tinfoil
a dozen 2" general paint brushes
a small plastic container
and possibly a heat gun
 
there is a fibreglass moulders just next to my dad's house, I could get them to do it but i'd need a template first, thats a bit tricky.
 
make the template yourself

remove the interior trim off the side of the car with which you wish to replicate

now fabricate the outside edges of your box so as it leaves you with a flat edge to mount your baffle and subwoofer to (you will mount fibrglass this into the backpiece to make one piece with sides and back

cover the area you wish to fibreglass with 2 layers of masking tape overlapping them so as no part of the fibreglass will stick to the car
(when you create the shape try to make sure it will pull out of the cabin easilly including the fabricated sides take care with square corners and angles as they are harder to shape and harder to fit back correctly )
once you have taped off the area you wish to use as a back piece then
use other materials such as bin bags to protect other areas of the car from spillage

cut the fibreglass matting into various lengths and widths and work from the outside inwards on your structure
put the matting in place and mix the resin at a 2% ratio of resin to hardener and simply paint the matting until it is fully covered and goes allmost see through ( if you use anything other than marine resin you will have to lightly sand the surface of each coat to get the next to bond properly)

you will need about three coats and then you should be able to remove the structure without it being damaged now add a nice piece of corematt
to the inside of the structure and again simply paint the resin in until it is soaked through (the corematt will take a lot more resin than normal matting but is significantly stronger than matting on its own )
now add one last layer of matting and there you have it a finshed backpiece

your backpiece should fit in and out of the cabin with ease and the front baffle should be able to stick on easilly also

now measure the internal volume of your sub enclosure using something like polystyrene beads (like in a beanbag) and a measuring jug
for a subwoofer needing 1 cu ft of enclosure space there should be approximately 28 litres

make sure your enclosure size matches your intended woofer if it is too large then fill the internals with something which will not reduce under pressure
if your enclosure is slightly too small use a material like dakron (polyester fibre filler) which has the effect of tricking the woofer into thinking its in a larger enclosure by slowing down the airspeed inside the enclosure
 
where should I get this material from, any good online suppliers?
 
if you have a fibreglass builders or boatbuiders near you
id just pop in and ask to buy about 10 litres of resin with enough hardener to mix at a 2% ratio (its usually 1% ) but goes off quicker with 2%
they should also be able to supply both the matting and the corematt
should cost you about 30-40 quid in supplies then its just your own time to make it
 
Thanks very much, i'm going to take the plywood front and get them to mount a rear panel made from fibreglass to it (to the GRP specialists next door to my dad's)