Custom fibreglass sub box made and fitted

[stapo69]

Thought I'd whore my ride out again with more pics for you!

Really like my full Bose set-up but just thought it lacked a bit of bass, basically was looking for an excuse to build myself a fibreglass sub box, always thought I could do it and now I have it turned out brilliant.

Basically I made up an MDF base, back and one side behind the rear light, then covered the wheel arch with tinfoil and covered with a layer of fibreglass, then popped this out of the car and trimmed to sixe. Then I suspended a ring for the sub to mount too made from MDF again and glued it in place on a couple of inch square lengths of wood, when dry, streched an old curtian over the whole thing to get nice uniform curves, then coated with resin, when hard the whole thing got 3 layers of fibreglass to harden it all up, over the top a couple of skim coats of filler to smooth it all off, picked up a sheet of blue suede to match the interior and covered it.

I removed the audi tool box/ cd changer compartment, tools now in spare wheel, changer bolted under rear shelf, then bolted the box in place, it fits a treat, nicely out of the way so boot is still fully useable, really happy with it, pity from the pics you can't really see the genuine carbon weave sub cone from Kenwwod, to keep the theme running through the whole car.

Coming next an Amplifier build of a similar design on the other side of the boot, and then a false black vinyl floor, with window through too neatly layed out tool kit. This will keep the black leather/blue suede/carbon theme running throughout the car.

Sorry to waffle on, I'm home alone again and bored!

 

[brendan]

looks pretty good, that.

but how do you know what the volume of your box is? does the bass still sound ok despite just going random on the enclosure size?

 

[Siena]

Looks good.

 

[Lee Goodall]

Good work

 

[g60leigh]

look the part

 

[Oranoco]

Looks better than my twin 12" Kicker box I just lobbed in my boot

 

[aragorn]

i've something similar in my avant, although i made it flat fronted (MDF), and positioned the front upright so it doesnt encroach into the boot space at all, then moulded the fibreglass round the entire side panel.

We measured the volume of mine (black bag and water ) and it came out at around 20L which is just below the minimum recommended by pioneer for the sub, some googling uncovered a nice trick whereby if you fill the box with wadding (i used the inside of a fibre pillowcase) it makes the box act like a larger enclosure so we did that, and it sounds pretty good.

i have some images online but the server is currently offline, once its back up i'll link them here.

 

[billybravo]

nice mate looks like a mint job ive made a few of these now

Well done and keep up the good work

 

[stapo69]

I don't know what it sounds like yet cos I have no amp to run it yet! This is just part one.

As for the volume of the box I spent quite a bit of time measuring as I went to keep as close as to the recommended volume for the sub, taking the inner measurements as a rough box shape and playing around with the sizes to get a rough volume, most manufacturers do allow a certain amount of tolerance for the encosure size, for this sub the recommended sealed enclosures are anywhere from 0.6cu.ft for tight bass, recommended size 1.0cu.ft, or up to 1.5 cu.ft for deep bass, so quite a bit of scope for many sizes to work, the graph they supply shows very little frequency difference using the different siz boxes they show. The easy way of course is nce the box is started fill it with water to give you the exact no. of litres.

 

[Oranoco]

I've always found these guys cheap and easy to deal with.

http://caraudiosecurity.com/shop/home.html

They sorted me out my Alpine 9812RB at a bargain price

 

[stapo69]

Ta for that, I have the amp all picked out, matched the power output with the sub to get the most out of the woofer, their prices are pretty good but have found someone a little cheaper.

 

[Oranoco]

Cool cool mate.

 

[ALPINE]

looks smart maty! nice job!

 

[rasA4]

stapo, nice job what size is the sub? and the RMS?

 

[andybnwc]

Is it new shallow mount kenwood thingy is it the KFC-WPS1200F or the 10"

 

[Siena]

I had a similar set-up in my '94 Audi Coupe S2.

It sat in the same position as Billy and Stapo's enclosures, where the full size spare wheel normally lived.

Was great, I don't take the credit though, as it was in the car when I bought it.

 

[stapo69]

It's not the shallow mount kenwood, it was going to be originally, but once I started building the box I realised I could get far more volume in the space than i thought, so bought the better 10" dual voice coil KFC-XW1024D, runs at 250wrms + 250wrms at 4ohm per coil. Peaks at 800w + 800w. Plenty for me. Like the sound from a ten better, bit punchier, tighter.

 

[aragorn]

if anyones interested, my websites back online:

http://lr90.org/Audi/stereo

 

[sitrials]

2 words...
carbon pimp!!
better than that other picture you sent me you dirty *******!

 

[stapo69]

It disturbed me deeply, I thought I'd share!

And no I cannot share it on here, you wouldn't wanna see it anyway! Trust me!

 

[Andy.B]

That is exactly what i want, sub one side amp the other... dont suppose you would want to make another pair lol I havent a clue where to start with moulded boxes

 

[stapo69]

I don't really have that much time sadly, I built this one on the sly at work as it is!

If you type "fibreglass sub box" into google it brings up quite a few good guides of how to do it, that's all I went by, it's pretty easy once you get going, just quite time consuming though cos of the amount of different layers and drying times, I just did a bit when and where I could, ended up taking me a few weeks cos of commitments and work, I've not even found time to start the amp box yet as it is!

Have a look though and give it go, it certainly is satisfying to show something off you built yourself! Hope this helps.

 

[Andy.B]

Good man im all up for giving it a go myself just need a good guide to start with I think I will be bookmarking a few pages this weekend when i get back in from work.

 

[stapo69]

Good on ya man! There are some great guides about. I meant to take more pictures and knock something up myself but kept forgetting, gimme a shout if you want any help. If you can find somewhere that'll do you a bulk fibreglass kit I'd go for that, bodyshop or somewhere like that, I just used Halfords biggest kit myself, but went through at least 3 of them to get it thick enough! Didn't work out so cheap that way!

Good luck, keep us posted.

 

[Broken Byzan]

I like it,i made a thinner style one for mine and only used a 10 inch sub so i could use facelift boot trims to mount it behind its nice and protected usuing a space that i dont use for anything else except the reversing sensor speaker

 

[Andy.B]

Yes i have a man in the fibreglass roofing and mold making business so should be easy to get a bulk lot of the resin and glass sheet.

 

[aragorn]

When i did mine i used a mates supply of resin and sheet. He had the sheet on a huge roll, and the resin in a 5 gallon drum. Buying it like that is more expensive due to the sheer quantity you have to buy, but its much much cheaper per sqm than the silly packs from halfrauds!

 

[Z82]

Looks better than my twin 12" Kicker box I just lobbed in my boot