Need help on building a box.

Ok Iam building a box for two alpine type S sws1222d and Iam going to build it sealed but I need help on the demensions. Alpine says it needs Recommended Sealed Box Volume : 0.85

it will help you if you convert that ft^3 into in^3 because most of your calculations will be in inches


12x12x12 is one cubic foot or 1728 in^3.

for 2 subs you wanna aim for 2 cf total

so you need to take your height length and width and multiply them by eachother
and then that will be your boxes cubic inches. make sure this is an inside dimension not outside. Then you need to subtract the subs displacement from that total cubic inches. and that will be your final cubic inches which can be translated into cubic feet.


only use 3/4" mdf for it too

the box size depends on the type of bass response you are looking to reproduce, and also the amount of power you are putting to the subs. For street pounders with big amps I build boxes to the max recomended by the manufacturer. a smaller box will give you tighter bass with less BOOM. for an all around box, shoot right for the middle specs

What type of vehicle is it going in and how much room do u have to work with

If this won't fit in ur ride let me know and i'll redo it! Here r the measurements for ur subs 1.25 cubic ft per chamber is required 4 the optimum performince!overall size is 28" wide 15-1/4 deep and 14-1/2 tall. The internal cubic ft is 2.51 total and 2.5 is what u need. Here's what u need to cut sides-3 pieces 13-3/4 x 13" top and bottom 13-3/4 x 28" and front and back 28 x 14-1/2 and begin ur partition at 13-5/8 from the end

andy i would just try to stay between 1 and 1.25 cf. just build your box to your space requirements.

its going in a 98 Chevy tahoe. Yea I was planning for about 1 and 1.25 cf for it. I was going to run a 600 watt jbl amp on them.

alpine said 1.25 per sub

i do enclosures everyday and if your just gonna go sealed nothing fancy. by the time you get a sheet of 3/4 mdf,something to seal the box,carpet,and glue.not to mention your time. you would be better to pay 40-45 bucks for a prefab box that is gonna be right on those specs (most are) and not bother with building one.just load your subs and spend the rest of the hour sittin in your driveway jammin your stereo and drinkin a beer.
just and opinion...
now if your gettin the wood for free or something just build the box like 30x14x14 comes up to right over 2.57 cubes and when you figure sub displacement you'll be right on.
if you want a pounder go ported like 36x16x16 with a slot port like 13.5 tall and 3 wide and probably 10-12 deep. will give you alot more output from the subs.
cya,vandy

Originally posted by vandycoot



i do enclosures everyday and if your just gonna go sealed nothing fancy. by the time you get a sheet of 3/4 mdf,something to seal the box,carpet,and glue.not to mention your time. you would be better to pay 40-45 bucks for a prefab box that is gonna be right on those specs (most are) and not bother with building one.just load your subs and spend the rest of the hour sittin in your driveway jammin your stereo and drinkin a beer.just and opinion...now if your gettin the wood for free or something just build the box like 30x14x14 comes up to right over 2.57 cubes and when you figure sub displacement you'll be right on.if you want a pounder go ported like 36x16x16 with a slot port like 13.5 tall and 3 wide and probably 10-12 deep. will give you alot more output from the subs.cya,vandy

Thanks alot man the reason Iam building the box my self is because iam building the front board contored to the wheel wells in the back of my tahoe and i have meterial from work to upholster the box my self. But thank you for the specs.