# Sub Enclosure: Box vs Wedge



## joms

Hi. I never really dwell in sub enclosures before as I always put my subs in a sealed small enclosure for SQ. However, I'm kind of interested to shift to SQL and would like to maximize output while retaining SQ as well as maintaining a small enclosure. Moreover, my brother who is more into ang SQL/SPL guy is also setting up a system. (He is new to car audio by the way). We will both be using this on a small/mid size SUV van, rear facing.

Anyway, given that the subs I will be using is a JL 12W7 and my brother a JL 13TW5 (to be powered by a JL HD750/1), can you kindly help me with the ff questions:

1. What is the difference, advantage, disadvantage in using a box enclosure as against a wedge type given that the enclosure is:

a) sealed 
b) ported 

BOX: (pic A)









Wedge: (pic B)











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2. Can i make a wedge type enclosure such that the wood behind the subwoofer will be very slanted? (makes it somewhat a shape of a triangle already). Is there a limit on how slanted the back board can be? (see Pic C and Pic D)

For the JL 13TW5: (Pic C)









For the JL 12W7: (Pic D)









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3. Is there a minimum distance from the rear of the speaker to the rear enclosure board? If so, what is it? Will 1" do on both sealed/ported? (see Pic D)

Thanks.

-joms



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JL 12W7:









JL 13TW5 (Shallow mount subs):


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## 5Speed

I'm not familiar if the JL Audio W7 & W5 use vented poles or not but in a sealed enclosure there is no difference as long as they contain the same net cubic feet of air space and if vented pole is used there is adequate venting behind the subwoofers magnet.

If the subwoofers are being installed in a slot ported enclosure with the slot facing the same side as the subwoofer I don't see how the shape of the box will change the sound output as long as it is designed properly (Both 2 cubic foot net, @ 32hz).

Basically Enclosure #A and enclosure #B can be built and tuned to sound the same.

I'm not as well versed in building enclosures as other are, and I've built mostly slot ported enclosures but I do not see an issue with a difference in sound.


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## joms

how about pic C and pic D? Is there no downside if I slant the rear part of the box that much? Also, can i just alot about 1 inch space from rear of the driver upto the rear of the enclosure as found in Pic D?

Thanks


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## 5Speed

I do not see an issue with the slanted rear on the W5 especially since it is in a sealed enclosure. Building a ported enclosure with a slant of that magnitude I imagine would not produce the desired results you were looking for. But in a sealed enclosure I see no problems.

Leaving 1" behind the driver is adequate space in my mind for the driver to vent itself.

Any other questions feel free to ask.

I'm surprised no other members have chimed in on this.


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## joms

hmmmm. why would a slanting back produce undesired results for ported enclosure? I'm planning to put my 12W7 in a slot ported box with a very slanted rear.










Also, what is the min distance from the sub front to the back of the car? Can it be 1" only or do you need some space?


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## don_chuwish

I'm sure the guys at JL have thought about it a bit. If these pages don't give you enough info you can certainly call them.

13TW5 ENCLOSURE SPECIFICATIONS

12W7 ENCLOSURE SPECIFICATIONS

- D


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## 5Speed

joms said:


> hmmmm. why would a slanting back produce undesired results for ported enclosure? I'm planning to put my 12W7 in a slot ported box with a very slanted rear.
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> Also, what is the min distance from the sub front to the back of the car? Can it be 1" only or do you need some space?


Read carefully the last picture he posted of the enclosure had a very high slant to it. I would imagine being slanted to a peak would make it harder to build the enclosure and get the tuning correct.

Then again if you were using round ports instead of a slot type it would make it much easier to build.


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## joms

I only chose slot ported because it was what is on JL's recommended port enclosure design. Would using round ports be more ideal?


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## Salad Fingers

Using a slant or "hatch" style box will minimize/eliminate the possibility of a standing wave. 

I'm pretty sure ported is not recommended for the 13TW5.

You should leave at lease 3" or 4" between the sub's surround and the rear wall.

Minimum distance between the vented pole on the W7 would be an inch or two, enough room for it to let the heat out from the voice coil.


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## joms

whats the advantage between slot and ported? JL recommends a slot enclosure... why?


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## jf2oo6

joms said:


> I only chose slot ported because it was what is on JL's recommended port enclosure design. Would using round ports be more ideal?


I am interested in the answer to this question. I will be building a ported wedge, and I am wondering if I should go with a round or slot port. I used the RE Enclosure Calculator, but the way they have the box setup looks backwards to me. It put the port on the slanted part. I would like to port to be in the front, the flat part of the box. 

Can I just use the plans from re audio, but move the port to the front instead of the back without changing the tune?

Im wondering about the round port because that would make the build much easier. Is there any difference in sound of round vs slot, when both are tuned the same.


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## glidn

this is a very interesting point you are asking/making here.

Due to the W7 being a damn monster I would go wedge or slot port Cube box not square.

But the 13W5 Try dual wedge shape. Ie wedge on either side and the opposing side the magnet needs to point directly in the middle.

I built a Box like that for Alpine Type 12" (1224D from memory). It went stupidly low and super clean. Blended really well with the front stage.

forgot to add, The box also makes a big difference about the surrounding environment (ie. the car)


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