Help with building Sub enclosures please!

[Lionheart]

Hi there,

I want to start building a sub enclosure by using MDF and sealing the inside with silicone (as helpfully answered by you guys not so long ago) However i want to make it as compact as possible.
I've decided its going to be 2 separate cheese-wedge shapes laying flat in the boot housing a 12" sub in each one - but is there any precautions to building an enclosure? like...

Does there have to be a certain amount of air space within the enclosure around the magnet?

And what could i use to line the breather hole on the enclosure? a plastic cup? an old speaker surround? does it need to be a particular shape?

Id like your inputs thoughts and experiences on this, thanks:D

[pugsport]

you can go out and buy ports from an audio shop for like £5 mate but if you do port the sub box then it has to be bigger than if it was just a sealed box.

yes there has to be a certain amount of space inside the box and it should tell you how many litre you need with the information you got with the sub and then use the rockford fosgate website to work out ho big it had to be in mm/inch or what ever you wanna use.

the rock website has a converter on it so will be easy to do mate.

i forgot to say that if your putting a port in the box then if its a 2inch port it need to be 2inchs away from the side of the box, the sub and the bottom of the sub box

[loudandproud205]

by using a plastic cup "known as ported" you need to increase air space not decrease

[Lionheart]

Thats some top advice mate, cheers for that (^^)

[Lionheart]

Im all for increasing spaces, but doesn't the sub treat the boot as a giant enclsure anyway? - or am i missing something?

[Lionheart]

exept for the "O" in enclosure...

[pugsport]

o did i put decrease the space did i and if i did i meant increase sorry

[b19c0l]

Rockford fostgate has a brillant secition on building sub boxes
http://www.rockfordfosgate.com/rftech/box_wizard.asp

It will depend on the sub your going to go for, Some reqire more space than others,
Get the space requirement for the sub your going to go for then build the box around it.
Its vital to get the box as best as you can

[Lionheart]

Thanks again guys, I'm much more clued up now (^^)