Custom 8" Sub Box build guide

[stargazer30]

Hey All,

Well after my last thread on my recent install I've been at it again.  The speakers are working a treat but I wasn't happy with the active sub.  It was good for its size but I wanted a more solid punchy bass, so I've built an 8" sub box and compromised some more storage space   s:cry: :cry: s:cry: .  This is a guide to what I did incase anyone wants to build one, hopefully it'll save the hassle I had to make one that fits and get the volume of the enclosure correct.  

This box is designed to fit in the drivers side bin.  You don't need to remove the bin lid or anything, it'll drop straight in.  It'll take an 8" Sub and has a volume of 0.33 cubic feet.  I used a JBL GT804D sub which needs 0.3 cubic feet to work and costs about £50.

Materials
1cm thick MDF for everything except sides
2cm thick chipboard for sides (to allow for screws)
silicone sealent
40mm chip board screws x 24
countersunk binding posts
short length of wire
Felt 70cm x 100cm
Glue (white pvc used in schools)

You can buy this lot for about £25   s:D s:D  

Cut out the MDF first, these sizes
Base   36 x 26 cm
Top   36 x 24 cm
Back   36 x 14 cm
Front   36 x 14.2 cm

then the 2cm thick chipboard
Side (slanted)   22cm top & 24cm bottom x 14cm

Then basically you screw it together, all the MDF panels sit on the chipboard sides and screw into it.


The side view shows the slight angle, you need this to stop it hitting the bin lid.


Also as you can see the inner of the box is sealed with silicone, it doesn't hurt to put some on chipboard before you screw the MDF on too.

Next on goes the top, you need to cut out for the sub first though.  The JBL one I used needs a 18cm hole.  Again use silicone before you screw the top on.


Once the silicone is dry sand the edges so no slight overlaps.

Then cut out the side for the binding post.  I did this by drilling a pilot hole and using a jigsaw.  The hole is 78mm (7.8cm) but check the post you use as it might be different.


Once built the external size of the box should be...
Base 36 x 26cm
Top 36 x 24 cm
Back 36 x 16 cm
Front 36 x 16.2 cm
Side 24/26 x 16 cm

Now the tricky bit, covering it with felt.  I painted the glue on with a brush and stuck the top first, turned the box upside down and did each side one at a time.  I did the bottom last.  Don't try to cut the felt out for the holes until the glue is totally dry.



With that out the way in goes the Sub and binding post, these just wire toegther and screw in, very easy


Finally heres a pic of it installed...


and my old JBL 4ch amp in the other bin which drives the whole install.


All in all took my about 4 hrs to build this over 3 days but I didn't hurry. I'm much happier with a traditional sub, even though this is small at 8" its certainly punches enough for the MR2 and my tastes.   s:) s:)    s:) s:)    s:) s:)

David

[s12vea]

It looks really smart! Be even better if you mount the amp under the seat and have a 8" sub behind each seat. Just an idea for next weekend just in case you get bored?!  s;) s;)

[markiii]

really nice finish, shame about the chipboard

[stargazer30]

It looks really smart! Be even better if you mount the amp under the seat and have a 8" sub behind each seat. Just an idea for next weekend just in case you get bored?!  s;) s;)

My amp won't fit under the seat, I did try    s:lol: :lol: s:lol:   I kinda like seeing the lightup JBL logo too, I know very sad!

[DannyN]

Don't worry no amps fit under the seat

[no1trancefan]

let me know if ever sell the box haha