plans for a 12" sub box

[PeterCorreale]

hey everyone, does anyone here have or know were i can get good plans to build a box for a 12" sub for my accord? any help would be cool.

[matts]

where do you want to put this box? just one 12"? i'll help you out with it.

[PeterCorreale]

thanks man, its just 1 12, a sony p5 series. i want to put it in the trunk of my accord, i want to know wuts the best box for my sub and its location. i want a box that will hit hard.

[matts]

you know those molded boxes that are vehicle specific? they are made for 10" but i wonder if you could cut the hole bigger. the one made for our accords fits in in the spot between the top of the strut mount, and the taillight, i don't know which side.
another idea that i had before i put in my strut bar was to get a piece of mdf, or maybe some aluminum, and cut it so that it was almost vertical right where the seat folds down, on the trunk side of those dividers. along with cutting a hole for the sub, you could also cut out most of the other material, and leave just enough for the sub to be supported.
it would be a really functional box. you'd actually have your hole trunk as enclosed space, and it would hit directly at you.

[PeterCorreale]

hey, i like the idea with the vertical peice of mdf, but im having trouble picturing it.

[matts]

ok, if you fold the back seat down, so you can see the trunk from the inside of the car, you'll see black plastic pieces that make it look pretty behind the seat. if you took them off, the one across the top pulls straight up, just a few clips, and the two side panels have 2 clips each that you can see. if you were to pull those off, you would see a metal frame that goes from the bottom of the seatback, up to the top. you could mount the wood right to that.
http://www.imagestation.com/picture/sraid102/pc347822ac5f3f7acf32124a8d6504707/f9b2e62c.jpg
the wood could look something like this, just so that there is enough support for the speaker. it would be a lot lighter than a full piece, plus you could still slide long things around it.

[bcramer915]

i dont know a whole lot about sub box designs, but im pretty sure that would not perform well....unless u had a freakin massive sub and a massive amp.......and even then....thats not a very good design sound wise

[matts]

it's not the best design, you would get a lot deeper sound out of a solid board, but with the sub facing you like that you'll find that you need a lot less power to shake the whole inside of the car. you'll also lose a lot less power to vibrations and such you get when the sub is facing somewhere in the trunk.
so yes, it's not the best, but it will work just fine, and keeps the trunk functional

[jaccord96]

having the sub face u like that will not give you the best sound....ever wonder why subs always face the trunk? well haveing the bass reverb off the trunk will greatly magnify it..usualy the closer to the trunk the better....also the right sized enclosure is key to good sub performance...a diference in a few inches can be detramental to the output. it isnt all about bigger with more power, you have to fine tune it like engine. check the paperwork that ur sub came with, it should have the cu in that it will perform best at, and try to buld a box as close to that as possible. if for cosmetic purposes it ends up too small, u can trick ur sub into thinking there is more air space by filling it with pillow stuffing.....or if its too big, tune it with pieces of 2 by 4s..or u can just use what looks best with crappy output....anyhow, good luck.

[PeterCorreale]

thanks for the info everyone! im gonna follow those dimensions that came with the sub for building a box. i was thinkin about buying one from like best buy or somethin, they had them there pretty cheap, wut do u guys recomend would work best for my car, the plexi glass enclosed box, or just a regular box?

[matts]

the plexiglass is called bandpass. i think the sound out of a regular box is much cleaner. you get some extra vibrations with the bandpass.

[PeterCorreale]

does the bandpass hit harder?

[Ricanstylz00]

I'm not trying to be anal but you should also look into speaker box interior volumes and how much your speaker can handle. All enclosures should be constructed of at least 5/8'' - 1'' MDF (medium density fiberboard) or material of comparable rigidity or better. With all enclosures, lining the walls with a damping material (fiberglass batting, polyfill, tar based spray, etc.) is recommended to reduce high frequency resonances.

To calculate interior volume multiply:

Width x Height x Depth x Thickness of box material = interior volume Cu Ft.

For example: A rectangular box for a single 12"

15.5 x 15.5 x 17 x .75 (3/4 mdf) = 1.76 cubic feet of interior volume

If your sub can't that much, then just reduce the size of your box configuration untill you sub and your box specs are almost equal without the box specs going over your speaker specs.

Sometimes I wish I never left the installation business. Anyways, let me know if you need anymore help or clarification.

[novtech95]

i'd go with 3/4 mdf at max because that shit is by no means light. i myself am not a fan of bandpas or ported boxes, dont know why but the sound just seems to come out so much harder and cleaner in a full mdf enclosure. also make sure to caulk all seams inside the box to prevent air leakage. other than that just build the enclosure to speaker specifications, and try to stay away from the extremes. like if the specifications say the recomended volumes are 1 cubic feet to 2 cubic feet, try and stay between 1.3 and 1.7. gets kinda risky when you get toward the recomended extremes.

[PeterCorreale]

i just finished my box today. it came out sick. my dad is a carpenter so he helped me make it. i made it out of mdf, i used aquarium silicone on it to seal it, and i painted it a black glossy finish. it came out really sick, im gonna try to get some pictures of it up soon.