box build design, need help from the pros

[mykwikcoupe]

Ok so I was browsing JL Audios website again and figured id be a good time tostart planning my sub install. Id like to use 2 of the 10W7 bescause I can use my 1000/1 and it saves on total costs. Now on there site they list a slot port design and that what Id like to build.

Im imagining the subs facing forwards tight to the back seat and the slots for each box in the middle looking kind of like there slot port power wedge design. Now I used to be a carpenter so i can build anything from wood and Ive built my own basic boxes for years, never anything like a slot port though.

Jl s site lists every possible size for my box but leaves out bracing. Im guessing a box nearly 2 feet deep has more baces than they show in there box specs.

If I wanted to do something stupid like modify the size spec to use more room height or width wise to better suit the accord trun volume, how would this change all other design characteristics?

Im wondering if I should just take 2 of there box designs, mate them in the middle and call it good or try to matters into my own hands. It seems as though some mods in this forum work in the audio field and Id like there thoughts. Thansk Mike

[89T]

additional bracing shouldn't be required,as long as you use a min of 3/4" mdf or particle board(depending on you're budget), use a good stout wood glue. as for volume goes try and pick a box with the characteristics you are looking for. changing volume changes the tunning freq of the box. in tis case changing the volume will also change the tunning freq of the vents also.

there is a way to get what you are looking for though.
for simplicity's sake, the box volume is 1 cubic ft. their dimensions are 12"x12"x12"
12x12x12=1728 cubic inches
1728 / 1728=1 cubic ft

or another example 2cubic ft
12"x12"x24"
12x12x24=3456 cubic inches
3456 / 1728=2 cubic ft

lets build the 1 cubic ft box.
take the volume in cubic inches and reverse the math.
say i want the box 14" high.
1728 / 14= 123.43
now i need a min. of 11" to fit one 10" woofer.
123.43 / 11=11.22
making you're box dimension
14"x11"x11.22".......does that make sense?
double check you're self.
14x11x11.22=1727.88 close enough to 1728.

as far as your vent goes you will do the same math
2"wide 12"tall 8"long(their dimensions.)

2x12x8=192

192 / 1728=0.111cubic ft.
192 / 14 high=13.71
13.71 / 2"wide=6.86" long
double check...14x2x6.86=192.08 / 1728=.111cf
new dimensions:
14"x2"x6.86"

this method is probably old school as fuck,seeing that i haven't installed professionally in about 7 years.lol
if you have any questions or want to post their dimensions vs the dimensions you want or want to just double check i am game.

i know there are other members with bass box and other programs to build custom boxs, lets hope they chime in also.
am i slippin?lol!

[mykwikcoupe]

ol makes sence. lets say the jl website lists a ported box as a slot port. Can you still use your general calculation to figure it for a round port or better not to mess with it?

[89T]

jl suggests a slot port, id stay with that.
besides you'll get port noise with a pipe vent.

[xxxfrankensteinxxx]

go to http://www.realmofexcursion.com/ great place

[Accordtheory]

Here's the site where I got my software.http://www.speakerbuilding.com/software/ I downloaded the boxplot program, it's basic, but seems to work pretty well. You can play around with box sizes and tuning frequencies pretty easily, you just have to get the specs on the subs. What I'd recommend for a car with a trunk (ie, not a hatch) is to have the subs facing toward the rear, with the ports facing the same way, and cut out the rear deck. Cutting out the deck makes the sound a lot more even and clear throughout the car, reduces rattling in the trunk, and makes the sound carry a lot more outside the car with the windows down.You could either make one big cut out and upholster it so you don't have a shitty looking metal edge exposed, or cut out a bunch of small sections and put grill cloth or some other acoustically transparent material over it. I learned this on an old caddy, I cut out most of the rear deck, bondoed/fiberglassed in a piece of mdf on top of what was left, and had 2 12s in that, with a thick ass fiberglass wall behind the seats to make the trunk into a giant box. I didn't like that though, because although it sounded ok in the car, esp at really low fequencies (like track 7 on dre's chronic 2001) it just didn't carry, and I like to piss off other random people with my bass. So then I cut out most of the deck, put some material similar to the oem deck covering shit on the mdf, molded it around the inside edges of the cut out with a heat gun, then glued it on with 3m spray on adhesive. It actually looked pretty clean. That sounded much, much better, and another thing I really liked about it was the wall between the seats and the trunk. I was originally planning on cutting it out, but once I turned my system up, I liked it because it further reduced the sound from slamming you in the back when you were in the back seat. It also might have actually helped the sound level overall too, I don't know. I personally hate sitting in the back seat when the driver wants everyone else to hear his shit, and all the sound has to go through Your body to get out. You can't even see straight, when for everyone else it isn't even loud, f that.

[mykwikcoupe]

well this car is typically just for me. Ive got a few rides and this one is mine. What I thought Id do is face the subs into the rear saet port facing the same direction and install a gas arm that can raise or lower the seat with a witch like the mini trucks do with the tailgate stuff. This way I can ride with the seat down and not have to pull it up everytime I get out of the car. I used the rear deck on a previous accord I had and I couldnt get the thin metal and rear taillight to stop vibrating to save my soul. I thought I tried everything.

After reading some previous threads on other sites about the 10w7 subs. When installed in the correct box, 2 of them is going to consume my entine trunk cavity. Im not down with that at all. Unless I can find a box design that sounds as good with all the highlights, Im gonna have to stick with a single sub

[Accordtheory]

I used the rear deck on a previous accord I had and I couldnt get the thin metal and rear taillight to stop vibrating to save my soul. I thought I tried everything.

That's what I'm saying, just cut it out, then there's nothing there to stop the sound or vibrate. But your idea is actually one I've wanted to try for a while too. It would definitely eliminated any rattling from sound pressure in the trunk..

As far as the JLs, there are so many good subs out there these days, it's almost harder to buy shit than good..I personally think jl is overpriced.

[mykwikcoupe]

overpirced yes, Ill agree but the looks and what Ive done to them in the past. Ive overpowered, over used and flat out destroyed them and they stand up to just about everything I can think of. Plus there so so so pretty.

My last box was 2 jl 12w6 in a I think a 4th order box. ports firing through the rear deck. I put extra 6 1/2 covers over the 2 middle holes in the deck and it sounded great. Hit low with 600 rms going to them and rattled like a cheap beer can