dose not meant the space req for the sub that u have ?
such as putting a small box so it can fit on the spare tire dip.

 

It will sound like crap... won't hit the deep notes right and will resonate at the wrong frequencies.

Don't do it!

 

Dose it have to meet the exact req or can i just be off by a few inches here and few inches thier ?

 

My experience has been that following the manufacturers specs will produce the best sound.

You can make smaller enclosures and stuff them with polyfill that will 'simulate' a larger enclosure to the speaker, but it's a crapshoot as far as what it will sound like.

Nothing sucks more than to spend a whole bunch of time making a kick ass box and then have it sound like crap.

Ideally, building a box using the manufacturer's specs to the 'golden rule' of speaker box design will make the cleanest sound.

They have a free golden rule speaker box enclosure program on this site:

http://www.ajdesignsoftware.com/speaker/

I used it to build my box and the sub sounds AWESOME. Hits the entire range like its supposed to.

 

If u buy a jl audio woofer u can put it where the spare use ta b.........jl's dont need large boxes ta wang at their best

 

A small box is going to give it more power handling, and decrease efficiency... You'll also end up with a bump, and it will be at different frequencies depending on the sub. You do lose lower bass extension, however, some subs are designed to go into tiny boxes, and they can still play the lower notes if you have enough power.... Diamond Audio M610's for instance... It can be as small as .3 cubic feet....

 

I've been looking at subs and the JL 10W6V2 in a seald box fits in just .75 cu ft. Its small enough for what I want to do with it...