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Caleb9107
11-22-2009, 12:50 AM
Well I have been playing around with different boxes and have come up with one I am hoping will work. It will be in an explorer holding two 12"s.
It is 4.2cu ft net tuned to 35 hz. The port length is 24.75 and I believe port area is right about 60 sq in(15 per cube). With this design and these numbers, does this sound like it will perform well? I am not looking for Sq or SPL per say.. I just want something to hit the lows and pound out some bass. I am NOT looking to put up numbers so that should not be a factor.

http://img504.imageshack.us/img504/6199/box1120092ddimensions.png (http://img504.imageshack.us/i/box1120092ddimensions.png/)http://img504.imageshack.us/img504/box1120092ddimensions.png/1/w950.png (http://g.imageshack.us/img504/box1120092ddimensions.png/1/)


http://img10.imageshack.us/img10/3482/box112009finishedin2d.png (http://img10.imageshack.us/i/box112009finishedin2d.png/)http://img10.imageshack.us/img10/box112009finishedin2d.png/1/w950.png (http://g.imageshack.us/img10/box112009finishedin2d.png/1/)

Any suggestions? Constructive criticism? I am all ears!

marcotheclepto
11-22-2009, 01:35 AM
the only thing id worry about is port width to height, its right on the "rule of thumb" 12-1 ratio.


edit: what heigth and width is the port? was thinking it was 24.75 wide, but thats the length , you may want to reconsider your port layout.

Caleb9107
11-22-2009, 02:56 PM
It is 40 1/4" wide(horizontal), 1.5" tall(vertical) and 24 3/4" long. For what purpose would you recommend reconsidering the port?

marcotheclepto
11-22-2009, 03:00 PM
you wanna keep the port to a 12:1 or smaller ratio. a port too short and too wide will have port noise.

Caleb9107
11-22-2009, 03:01 PM
I thought the rule was 12-16:1? Or is that a myth?

mobeious
11-22-2009, 03:05 PM
why not do 2 vertical port on each side of the box 1.75 wide

marcotheclepto
11-22-2009, 03:05 PM
I thought the rule was 12-16:1? Or is that a myth?

that rule, is sq in per cubic ft, your good there, what im speaking of is. a port width to port height a completely different topic. ex. a 15x4 port would be ok. however a 40x1 port isnt tall enough. air will be too compressed. make sense? maybe someone better versed can explain it better.

marcotheclepto
11-22-2009, 03:06 PM
why not do 2 vertical port on each side of the box 1.75 wide

ah, maybe you can better explain it... :)

Caleb9107
11-22-2009, 03:11 PM
I see your point marco.. height to width of the port ratio.... So for it to be 40" wide.. it would need to be roughly 3.3" tall?

marcotheclepto
11-22-2009, 03:27 PM
I see your point marco.. height to width of the port ratio.... So for it to be 40" wide.. it would need to be roughly 3.3" tall?

yes. :)

Caleb9107
11-22-2009, 03:35 PM
Ahh.. thanks! Guess I have some more figuring to do! I'll post up some more when i get that far!

Caleb9107
11-24-2009, 12:02 AM
Well I went with a different design this time. The box is 2.23 Cu. Ft. net per chamber. Each is tuned to roughly 34 Hz. Port length is 29.5" long. I have about 14.7 sq in of port per cube. Port Height is 16.5". Port width is 2". I plan to flush mount but the drawing is not showing that currently.

Ok, the question is.. Does this meet standard requirements(ratio's?) or anything anyone else can point out. In general, constructive criticism is what I am looking for, or will this box work like it is?

The plans.

http://img256.imageshack.us/img256/5937/box112309planning2d.png (http://img256.imageshack.us/i/box112309planning2d.png/)http://img256.imageshack.us/img256/box112309planning2d.png/1/w958.png (http://g.imageshack.us/img256/box112309planning2d.png/1/)


Fully drawn.

http://img687.imageshack.us/img687/8779/box1123092d.png (http://img687.imageshack.us/i/box1123092d.png/)http://img687.imageshack.us/img687/box1123092d.png/1/w958.png (http://g.imageshack.us/img687/box1123092d.png/1/)

Thanks,
Caleb

marcotheclepto
11-24-2009, 12:40 AM
didnt check the math on the box, but design looks solid :) much better off here

edit: checked your math, looks good.

Caleb9107
11-24-2009, 12:51 AM
Thanks Marco! I knew I would come up with something I was satisfied with as well as the laws of car audio. Guess it's time to start building!

marcotheclepto
11-24-2009, 12:59 AM
Thanks Marco! I knew I would come up with something I was satisfied with as well as the laws of car audio. Guess it's time to start building!

might wanna try a few smaller kerf pieces out first, before using it on the large pieces there.... cut as deep as you can.... if youve got expereince with it then nvm haha gl with your box :)

bassman3
11-24-2009, 02:35 AM
I see your point marco.. height to width of the port ratio.... So for it to be 40" wide.. it would need to be roughly 3.3" tall?

The best thing to do is to graph it (for air port velocity) and take a look at the graph to see if port noise will be present. Not going by a 12:1 ratio. :)

Caleb9107
12-02-2009, 12:16 AM
Well I am in the process of building now and have a question about the connectors. I am going to need to wire the subs together as of now..but, Should I just go with terminal cups incase I decide to wire them each to individual channels at some point?

Caleb9107
12-02-2009, 11:15 PM
Bump.

Any opinions on terminal cups vs not? If not, what alternatives would you suggest..

marcotheclepto
12-02-2009, 11:40 PM
terminal cups will work. bass threaded rod with bolts will work... doesnt matter really. having one cup per vc is a nice bonus allows you to rewire the subs on the fly.

Caleb9107
12-02-2009, 11:59 PM
So if I am running 2 DVC's I would need 4 cups?

marcotheclepto
12-03-2009, 12:09 AM
So if I am running 2 DVC's I would need 4 cups?

dont need them just saying its always nice if you change amps/ compete and change wiring often not at all necessary merely suggesting an idea :)