paraordnance
New member
I started building my stereo a year ago when I finally had enough listening to JBL Synthesis for 5 years that I owned my 2004 4Runner. And this summer I finally decided to tackle the subwoofer enclosure. Right from the start I knew that all my stereo components will be away from eyesight. No flashy speaker grills, exposed tweeters, crossovers, cables, amplifiers or subwoofer boxes should be visible or in direct sight. I had experienced car stereo equipment theft before and was trying to be with my install, as stealth as possible. Two sets of 6.5" components in doors were providing some bass, but the low end thump was missing. I didn't want any subwoofer enclosures taking up my cargo area, I also wasn't prepared to spend $800 on the Stealthbox which still protrudes and sits over the wheel. I decided to build my own custom subwoofer enclosure in exact location where factory JBL subwoofer was. Building custom enclosure from MDF and fiberglass is a lot of work and patience, it took me over a month to complete this job but I was not in rush. I knew that the space is limited and I had to choose shallow mount subwoofer to achieve this. My top choice was 10" JL Audio 10TW3D4 400 Watt dual voice coil subwoofer with a mounting depth of just 3.5”. I bought one around Christmas 2014, on sale, brand new in box for just $250 CDN. A steal and a lot of bang for your buck, literally.
First I removed the rear right piece of trim which covers original subwoofer and amplifier.
Compared old vs new side-by-side
I installed subwoofer amplifier under the passanger seat. It is tiny (7x9") Hertz HCP1D which delivers 700 Watt RMS at 2 Ohm load, little too much power for this subwoofer but its always better more than less.
Next step is to remove original subwoofer box and amplifier combo. It looks like a plastic toy but original box is engineered and build quite well. It is also around 16 liters of volume and JL 10TW3 only needs 0.5 cu.ft which is around 14 liters. I figured if I replicate outside dimensions of the original box I should be pretty close and have a nice fit.
You can see from the pictures above that the shape of the void space behind rear-right quarter panel has irregular volume and tapered to the top and bottom from the middle. In the middle, where it is widest, we got about 7" clearence, and no more than 4" on top and bottom, ouch.... From that point I knew I will have to use fiberglass for rear wall to confront to shape of the quarter panel. I don't think with MDF alone this project is feasible, there is just not enough room.
First goes sound deadening everywhere, I used box of Hushmat (10300) for cargo area since it was cheapest. 10 sheets - 12" x 23" for 19 sq. ft coverage, overall on truck I used 50 sq.ft of this stuff lining each door on inside and outside as well as complete cargo area and around subwoofer enclosure. Don't skip on this, this is very important step for SQ if you don't like rattling body panels.
Due to custom nature of this enclosure I started with piece of cardboard which I later trimmed and used as template for front wall of enclosure.
Old vs new sub dimensions
New subwoofer has slightly less mounting depth compare to the old one, so I'm not worried of clearance issues
First panel sizing up
Other panels measured and cut
Enclosure starts to take shape, screwed and glued together. I don't remember exact dimensions since I had to cut each piece to fit
Once the MDF (I used 5/8" due to the small size of panels) box is built it was time to start fiberglass work
First I removed the rear right piece of trim which covers original subwoofer and amplifier.
Compared old vs new side-by-side
I installed subwoofer amplifier under the passanger seat. It is tiny (7x9") Hertz HCP1D which delivers 700 Watt RMS at 2 Ohm load, little too much power for this subwoofer but its always better more than less.
Next step is to remove original subwoofer box and amplifier combo. It looks like a plastic toy but original box is engineered and build quite well. It is also around 16 liters of volume and JL 10TW3 only needs 0.5 cu.ft which is around 14 liters. I figured if I replicate outside dimensions of the original box I should be pretty close and have a nice fit.
You can see from the pictures above that the shape of the void space behind rear-right quarter panel has irregular volume and tapered to the top and bottom from the middle. In the middle, where it is widest, we got about 7" clearence, and no more than 4" on top and bottom, ouch.... From that point I knew I will have to use fiberglass for rear wall to confront to shape of the quarter panel. I don't think with MDF alone this project is feasible, there is just not enough room.
First goes sound deadening everywhere, I used box of Hushmat (10300) for cargo area since it was cheapest. 10 sheets - 12" x 23" for 19 sq. ft coverage, overall on truck I used 50 sq.ft of this stuff lining each door on inside and outside as well as complete cargo area and around subwoofer enclosure. Don't skip on this, this is very important step for SQ if you don't like rattling body panels.
Due to custom nature of this enclosure I started with piece of cardboard which I later trimmed and used as template for front wall of enclosure.
Old vs new sub dimensions
New subwoofer has slightly less mounting depth compare to the old one, so I'm not worried of clearance issues
First panel sizing up
Other panels measured and cut
Enclosure starts to take shape, screwed and glued together. I don't remember exact dimensions since I had to cut each piece to fit
Once the MDF (I used 5/8" due to the small size of panels) box is built it was time to start fiberglass work
