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Discussion Starter · #1 ·
ok im thinking of building a box for under the rear seat in my 2003 ex cab silverado, i have 2 12 inch l7 kickers square subs, i plan on liftin the rear seat, i dont want it to tall but probally 3 inches max, i want a ported box, im not sure what the max deminsions would be and also how much port, i would probally do a common chamber port in the middle. any suqgesions, the hard part will be probally is going over the humps. anyone have pics of there rear seats lifted with sub box?
 

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haz 12"s!
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Welcome to what everyone wants. I tried going this route and there just isnt enough airspace for a ported box for 1, let alone 2. Even lifting the rear seat 2" I could only manage 2 cu ft with 3/4" MDF.
 

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Loves yoga pants
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311615_91.jpg


PICT0012.jpg


Here was what i had in my 99. 2.5 cu ft. with driver displacement. Rear back of seat was lifted 3". Box made of 3/4" MDF...running 3 Treo TSX 10's sealed. Removed the seat bottom springs from seat and added foam and factory cloth to top of enclosure. Somewhat comforable to ride on, but looked like a stock seat with a box under it...lol...far from it.
 

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Discussion Starter · #7 ·
well im not sure, i just want them showing, also if there facing down, i would think they wouldnt sound as good cause the sound would be hitting straight to the floor
 

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S-Marts Top of the Line
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well im not sure, i just want them showing, also if there facing down, i would think they wouldnt sound as good cause the sound would be hitting straight to the floor
obviously you've never heard down firing subs.

but yea, if you cram 2 12s under your seat your system will sound like garbage....doesn't matter which way they face. you simply don't have enough air space.
 

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I have 2.0ft^3 for my single 12 without raising the seat, that's about the most you can get without raising or having a box that sticks out past the seat
 

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I raised my seat 2 inches and then built a box using my old subthump box as a template. I was able to obviously add 2 inches to the height. I kicked out the driver's side 3 inches because subthump's design left that under seat space unused for some reason. It does not stick out front any further. I then added a chanber on the back that goes towards the back wall of the truck. This chamber is approximately 5 inches by 6 inches and goes the whole width of the box. My box is sealed and based on a volume calculator, I have 1.23 per side, which is ideal for my JL 12w3's. I did lose a little volume because I used 3/4 inch MDF and subthump built theirs with 1/2 and 5/8. The subs reach lower depths and it was worth it to me to build it since I like working with wood. The seat belt receivers still work as they should and I also have the seat fold down trick in there since the seat was raised.
 

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Officially Tucking Tire
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thor do you have any pics of your box?
:word:


also glass the bottom to gain a bit more space.
im trying to fit 2 dc lv4xl 10s under my seat

dc next to a type r.:D
4.jpg
 

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Loves yoga pants
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ok im thinking of building a box for under the rear seat in my 2003 ex cab silverado, i have 2 12 inch l7 kickers square subs, i plan on liftin the rear seat, i dont want it to tall but probally 3 inches max, i want a ported box, im not sure what the max deminsions would be and also how much port, i would probally do a common chamber port in the middle. any suqgesions, the hard part will be probally is going over the humps. anyone have pics of there rear seats lifted with sub box?
it just dawned on me you're in tulsa too...

go talke to Mike Hudson the owner of Boomer's audio. He will build you a custom box to your wants/needs.
 

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CRF rider, I dont have any pictures, sorry. Basically, from the side profile, the box looks the same as most underseat boxes, except the 6x5 square chamber on the top part of the backside. The 6x5 chamber only touches about the top 3 inches of the top back portion of the box. Does that make sense? I built both boxes first before attaching them to each other. I then put them both in place and tested the seat for fit by moving it up and down. Remember, I raised my seat 2 inches, so you must raise it first before test fitting. Once I had both boxes in place and the seat working as it should, I marked the box as to where I would attach them to each other. I then took them out and screwed them together and test fitted again. It was a tight fit and only got tighter once I carpeted the box. Hope this helped.
 

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Officially Tucking Tire
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