jl w7’s, which box should i go with?
Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=134332
Printed Date: May 19, 2024 at 5:33 AM
Topic: jl w7’s, which box should i go with?
Posted By: deeryders
Subject: jl w7’s, which box should i go with?
Date Posted: June 07, 2013 at 10:00 PM
I have 2 12inch w7's (pushed by a logic tx4000D with epicenter and clarion crossover)currently in a ported box stuffed with poly-filler. I am not sure what specs are. I have a 2009 Altima Sedan so I have fairly enough trunk space. I wanted to get a better frequency response from my subs, in other words I want to be able to get my subs to hit as low as possible. Someone suggested on building a bandpass enclosure. I know nothing about enclosures and was wondering if I can get some advice.
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Replies:
Posted By: DYohn
Date Posted: June 08, 2013 at 11:03 AM
W7s are outstanding woofers. JL Audio recommends using either 1.375 cuft sealed per woofer, or 1.75 cuft ported at 37Hz per woofer. I cannot recommend bandpass - turning those monsters into a one-note-wonder would be a shame. ------------- Support the12volt.com
Posted By: deeryders
Date Posted: June 08, 2013 at 11:14 AM
So two individual boxes? You recommend just following what's on the manual. Anyway would it make a difference if I port the box in the back? I'm getting really bad trunk rattle even with 3 layers of dynamat and foam sealed trunk. What do you mean one note wonder?
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Posted By: DYohn
Date Posted: June 08, 2013 at 11:22 AM
No, you don't have to use individual enclosures, although using a divider to create two separate chambers in one enclosure is ofter the easiest way to go about using two woofers if you don't have design software. A bandpass enclosure is called a one-note-wonder because 100% of the output is created by the port, so it produces a very narrow band of sound - AKA one note. This can work well for SPL competition but not always a good solution for listening to music. As far as your trunk rattling, that can requires a lot more than simply using Dynamat if you really want to stop it. Often only the careful use of welding torches can stop all the rattles. Or turn the volume down... :) ------------- Support the12volt.com
Posted By: deeryders
Date Posted: June 08, 2013 at 3:31 PM
Nissan FTL. lol so based on everything I should build a ported box tuned down to 37hz. How do you feel about the port being on the back of the box?
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Posted By: deeryders
Date Posted: June 08, 2013 at 3:37 PM
This is the box they are currently in ATREND ZV12D-BLACK
https://www.amazon.com/Atrend-Zv12D-Black-12-Inch-Chambered-Enclosure/dp/B0013MT604 ------------- MECP Certified
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Posted By: DYohn
Date Posted: June 08, 2013 at 3:37 PM
deeryders wrote:
Nissan FTL. lol so based on everything I should build a ported box tuned down to 37hz. How do you feel about the port being on the back of the box?
If it's in the trunk it doesn't really matter where the port is located. Just make sure there is plenty of room between the port and the nearest surface, say 2X the port diameter. ------------- Support the12volt.com
Posted By: deeryders
Date Posted: June 08, 2013 at 3:40 PM
This is the box they are currently in ATREND ZV12D-BLACK
https://www.amazon.com/Atrend-Zv12D-Black-12-Inch-Chambered-Enclosure/dp/B0013MT604
------------- MECP Certified
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Posted By: DYohn
Date Posted: June 08, 2013 at 3:58 PM
Hard to say what vent frequency that port creates. It looks like about 2 cuft per chamber, but what are the dimensions of the port? ------------- Support the12volt.com
Posted By: deeryders
Date Posted: June 08, 2013 at 4:04 PM
No one has proper dimensions I emailed the company. Will let you know when they get to me.
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Posted By: soundnsecurity
Date Posted: June 08, 2013 at 9:11 PM
hey man as far as the trunk rattle goes ill tell you a nice trade secret. loosen the latch which just looks like a loop of metal and move it just a tiny bit farther away from the clamp that holds the trunk shut. this will make it so that the truck is held together a lot tighter and might take a bit of adjusting until you find a good balance of tight trunk lid and how easy it is to close, if you move it too far then you will have to slam the trunk to make it latch. this little trick should take at least half of the trunk rattle away and it wont cost you a dime.
also when it comes to rattles people dont realize that a lot of what you hear is on the outside of the car. if you really want to get rid of all rattles then you need to listen carefully to what is making the noise and figure out how to stop it. usually the best idea is to find things that are rattling against each other like tail pipes and their mounts or other pieces of metal that are close together, find a way to get something in between and the rattle is done. spray foam and rubberized undercoating are my favorites.
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Posted By: DYohn
Date Posted: June 09, 2013 at 10:08 AM
According to their website, that enclosure is 2.25 cuft gross per woofer and the vent is tuned to 38Hz, so it should work pretty well with W7's. I suggest you might need to add some bracing and seal up the seams depending on how it's built, but size-wise it looks OK to me.
ATREND website------------- Support the12volt.com
Posted By: deeryders
Date Posted: June 09, 2013 at 3:00 PM
Yea but isn't the interior volume per chamber is slightly larger then what is I tended so will it sound better if I get it closer to specs meaning somehow lessen the space inside each chamber
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Posted By: soundnsecurity
Date Posted: June 10, 2013 at 7:07 AM
W7's actually like big boxes. i used to have an 8W7 and i had it in a 1 cubic foot ported box which is huge for an 8 and it sounded awesome. the manufactures specs are a good start but depending on the type of install and what you want to get out of the subs these specs can be adjusted to fit the listener.
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Posted By: DYohn
Date Posted: June 10, 2013 at 9:25 AM
deeryders wrote:
Yea but isn't the interior volume per chamber is slightly larger then what is I tended so will it sound better if I get it closer to specs meaning somehow lessen the space inside each chamber
It will be fine. ------------- Support the12volt.com
Posted By: deeryders
Date Posted: June 10, 2013 at 11:33 AM
Cool one last question. What about having poly filler inside.
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Posted By: DYohn
Date Posted: June 10, 2013 at 1:25 PM
deeryders wrote:
Cool one last question. What about having poly filler inside.
Should be no need. If you are concerned that the enclosure is not dead enough, get a can of truck bed liner (like Rhino Liner) and spray it inside the enclosure to cover the walls. Let it dry overnight before you mount your woofers. ------------- Support the12volt.com
Posted By: lucasoil4u
Date Posted: June 18, 2013 at 10:20 AM
Poly fill isnt necessary if you have the space to build a nice box.
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