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Yellowsentragirl said:
"If ported, how about a slot port, centered between the two subs?"

"If ported, what port opening area are you targeting?"
Do a google search for "winisd" its a ported box building program (freeware even) You enter your sub's TS parameters and it will give you some port dimensions for whatever frequency you wish to tune your box to.
 

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It's Delux son, Delux
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Discussion Starter · #262 ·
I already have all the tuning stuff figured out

I was thinking about putting a center divider, seems to be smarter...at least if i blow a sub...can't be THAT much harder to build....right?


""If ported, how about a slot port, centered between the two subs?"
Just asking you where you want the port"
yeah I figured that but wanted to make sure...slot port through me off



""If ported, what port opening area are you targeting?"
How much port area do you want? For a pair of 10L7s I would go for around 60 square inches"

What is a port area? like the amount of area a port takes up? I figure that this affects SQ right?
 

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yeah it's always a good idea to put a center divider when you have a box with multiple subs, it's not that much harder to do at all, it's just an extra board you have to put in the middle of the box.

a slot port just means a rectangular port made out of mdf, instead of a round port made out of say, pvc.

The port area is the cross sectional area of the port. It does affect sound quality somewhat, basically if the port is too small, the air will be moving too fast and you'll get sort of a whistling sound called port noise. So you want the port large enough where you won't get noise, but not too big because the your box becomes huge (the larger the cross sectional area of the port is, the longer it has to be to keep the tuning the same, which takes up more room and makes the box bigger).
 

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35hz would probably be a good compromise


and in louder what do you mean?
um, it's pretty self-explanatory....if you tuned to 45hz the subs would be louder than if you tuned at say 35hz, but it wouldn't sound as good
 

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It's Delux son, Delux
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Discussion Starter · #270 · (Edited)
I've resurrected the thread....

I'm back...not sure if I updated but everyone who offered or i was going to pay haven't gotten back to me in 2 months...so i'm on my own building a box...i found some good websites and did some calculations...I just want someone with experience to check my numbers...

SO using this website

I came up with these numbers

So my calculations are:
1.75cu. ft per sub which is 3024cu. inches
The port is 2.75''x 11.25" and 17.75" long so the volume is 549.1 cu inches
The displacement of the sub is 1830cc which is 111.8cu inches

so the total cu in needed is: 3684.9cu inches or 2.1324 cu ft PER sub... so together i'll need 4.2648cu ft [7369.57cu inches]

Then the guy says to subtract the thickness of the MDF from the total available space...so i'll get:

35 -1.5 = 33.5in
14 -1.5 = 12.5in

so 7369.57 divided by 12.5 = 589.5656
589.5656 divided by 33.5 = 17.5989 inches deep

so my box should be 35x14x17.5

NOW...I want to put a center brace/divide the subs so they are in separate chambers...would i subtract 35 - 2.25 because of the extra .75 of MDF in the center?



And also...i've sorta abandoned NF and haven't been on in months but why am i back at 244 posts?? I was at like 600!
 

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your numbers look fine, just a few questions

1 - you have the box height as 14", which makes the internal box height 12.5", yet your port is only 11.25" tall? Where is that extra 1.25" above or below the port going to go? You could build it this way, but it would take a lot of extra wood to limit the port height to only 11.25" while the box is 12.5" tall, it would be much easier to just make the port 12.5" tall, and cut the width to 2.5" to keep the same port area and tuning.

2 - when you did the dimensions, the 17.5" that you came up with is the internal dimension, you need to add 1.5" to get the external dimension, so the box will be 35x14x19

3 - yes if you add a center divider you need to subtract 2.25" instead of 1.5" on the width like you thought, but if you make a center divider you'll need to have 2 ports, one per side, so make sure you account for that. And make sure you account for the volume taken up by the port wall, you did the volume for the port, but the .75" wall running the length of the port takes up space too.
 

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It's Delux son, Delux
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Discussion Starter · #274 ·
whew..yeah...

I really didn't even think about the port hieght...I just blindly plugged in numbers...

I was under the impression that the subs would sound nicer if they were in seperate chambers, each with thier own port... is this correct?


Redo of sub calculations:

still 1.75 cu. ft per sub which is 3024cu. inches

The Port ...this is what i didn't understand. Kicker says basically that 2.75''x 11.25" and 17.75" long so the volume is 549.1 cu inches...
you said to cut down the 2.75 to 2.5 and raise the 11.25 to 12.5...but those calculations get a volume of 554.68cu
inches...i know that's just a little but...

The displacement is still of the sub is 1830cc which is 111.8cu inches


35 - 3.75 [0.75x 5 which includes center divider,end pieces of mdf and port pieces] = 31.25
14 - 1.5 = 12.5


so 7369.57 divided by 12.5 = 589.5656
589.5656 divided by 31.25 = 18.86 + 1.5 = 20.36...so 20.5

and the last part...i'm not clear about the volume the port wall takes up...what would that be?/how do I get it?
 

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honestly the best thing to do would be to draw it out so you could get a graphical view of what it will look like, then the port wall displacement and everything will just fall into place.

as for the port, you're right, it should actually be a 2.475" width, but I just rounded that extra 1/40 of an inch off. You said this is the size that kicker recommends? Do they recommend this size port for 1 sub or 2? If it's for 2 then you can use it, but you'll have to have the subs in a common chamber box with this 1 port. If it's for 1 then you can divide the box like you wanted to do (it's always a good idea) and you'll need 2 of these ports, one for each chamber. Or you could always just come up with your own size port using winisd or bassbox pro
 

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Discussion Starter · #276 ·
Yeah I ended up drawing it out to get all the pieces of MDF that have to be calculated into the box...

The port size that kicker suggests is for one sub so I was planning on putting a center divider

So my box should be 35x14x20.5....sound right?

How do you determine the tuning if you're not using a program?
 

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yeah that sounds about right

There are equations out there to determine the tuning, I think one of them is on JL Audio's website. They're pretty complicated, it's normally easier to just use a program because you just plug in the box size, tuning frequency, port area and number, and it will give you the length, then you can just tweak it how you want.
 

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no need to re wire

hey man, i did it all myself and if you go on ebay they have service manual with all the spec v wiring diagrams for all the stereo systems made. if you look on the stock amp in the trunck there are two plugs one is the imputs from the deck, and one is the outputs to the speakers. if you want to put in amps, just hook them up to the output wires. you will obviously have to cut all the wires, just leave enough length to hook your plug back up if you ever sell the car. the diagrams are pretty user friendly.
 

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Discussion Starter · #279 ·
gabester222 said:
hey man, i did it all myself and if you go on ebay they have service manual with all the spec v wiring diagrams for all the stereo systems made. if you look on the stock amp in the trunck there are two plugs one is the imputs from the deck, and one is the outputs to the speakers. if you want to put in amps, just hook them up to the output wires. you will obviously have to cut all the wires, just leave enough length to hook your plug back up if you ever sell the car. the diagrams are pretty user friendly.
Sorry but what the hell are you talking about? obviously you haven't read any of this thread because that's already been asked, answered and installed.
 

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help with a decision

I need help to find two 8" subs.. i have a kenwood 800 w amp and i have very little space just need two eights for my crew cab.. i already blew one set of subs, and i dont want to waste any more money... thanks
 
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