FJ60 Enclosed Rear Quarter-panel Sub-woofer Build (1 Viewer)

[cam2ski]

I have been meaning to post this for well over a year now, as a result, some of the parts I used may be discontinued.

I wanted a decent sound system with an enclosed subwoofer but I didn’t/don’t want to modify the interior nor did I want to give up any cargo space or stock equipment functionality.

To select the components I read some reviews and chose whatever I thought would work best for my situation without being over-the-top expensive.

Components:
10” Driver: Pioneer TS-SW2502S4
Amplifier: Pioneer GM-D8604
Head: Pioneer MVH-X580BS
6” Front Speakers: Polk Audio DB652

After a year and a half of use, I am pretty happy with all of the components apart from the head. Single din was a requirement and I didn't want one with a slide-out screen (seemed more likely to break under rough conditions) so my options were rather limited. It does its job well enough but it feels a little cheaply made, it's not the easiest to navigate, but most importantly, the display is too basic and very difficult to see during the day. If I were to do it again, back in early 2018, I would have tried the Alpine CDE-HD149BT instead.

The amp is mounted in the other rear quarter-panel cavity. I hope to post pics of that as part of another post soon.

Additional Materials:
Highest quality ⅝” Baltic birch plywood
Wood glue
Stain
Polyurethane
Polyester fill/stuffing
M6 Rivet nuts
Allen driven M6 flathead machine screws (black oxide)
Binding post banana jacks (gold)
6 GA (i think) speaker wire

Build album also posted here:

Money shot first.
Covered, complete, and installed

Started by removing plastic push retainer hardware and drilling out the existing holes to fit M6 (i think?) rivet nuts

Removed the ribs

 

[cam2ski]

A lot of steps to cover here
1. Traced the existing trim board onto the highest quality 5/8" (or whatever the metric conversion is) Baltic Birch that could be sourced
2. Trimmed around the wheel well and rear seat lock housing until satisfied with the fit
3. Threaded in hardware from the back sides of the rivet nuts so that they stuck out far enough past the mounting surface to mark the wooden panel
4. Covered the bolt tips with chalk (graphite would work too)
5. Pressed wooden panel into place, firmly tapping above all of the protruding hardware
6. Center punched the resulting marks on the backside and drilled holes slightly larger than the selected hardware. Used a drill press to get as close to 90° as possible

1. Created a cardboard template to utilize as much of the cavity as possible, while still maintaining the ability to install and remove the panel with some ease
2. Using the holes as reference points, transferred the box shape onto the back of the panel

Some volume calculations

Using the template, cut out the back of the box

Moderately happy with this precision

 

[cam2ski]

Cut biscuit slots to help line up all the sides during glue-up

After much measuring, finally committed to a depth and cut the sides. Extensive test fitting continued

Cut corresponding biscuit grooves in the main panel

Cut driver hole prior to glue up

Glued up!

 

[cam2ski]

Test fitting did not go well and it was determined that the top edge of the rear of the box was hitting the external rear quarter-panel

Fortunately, this was discovered prior to glue up and additional material was added to the box interior (visible in first stain pic) to compensate for any weak spots a corner trim may create.

Trimmed with circular saw

Multiple angles and taper utilized to trim as little as possible and fit the contour of exterior body panel

Finally fits right.
Also, machine screw attachment holes had been countersunk at this point

 

[cam2ski]

An import part of this design is maintaining the functionality of the rear washer system using the OEM hardware.

1. Used original body panel to trace hole
2. Routered out notches required by hardware

Chamfered back for ease in hardware installation and functionality when complete

Hardware in and tabs bent back to secure

Cover fits well!

Outer exposed edge chamfered at 60° for aesthetics and functionality

 

[cam2ski]

Two-tone design. One coat ebony stain

One coat grey stain

Test fit after several coats of polyurethane, sanding between every coat

 

[cam2ski]

Installing audio hardware and wiring

Also seen here, multiple coats of primer and grey spray paint to protect the back and box

Sub box stuffed with polyester fill

Driver wired up and mounted using included hardware or possibly upgraded hardware

Covered, complete, and installed

 

[g-man]

riv nuts is a great idea to beef up the hardware to secure the larger heavier wood panel. Looks great.

 

[g-man]

Are the rivet nuts pressed into place? What tool is used?

 

[cam2ski]

Yes, pressed (pinched onto the sheet metal) in. I borrowed the tool from a friend so I don't remember the exact model but it was something close to the Astro Pneumatic Tool 1442 13” Hand Rivet Nut Setter

 

[Skniper]

Awesome idea and looks very well executed. Never understood having a goofy woofer box floating around the cargo area always in the way.
Nice write up.

On your shackle reversal your shackles are at a crazy past vertical angle, how’s it ride?

 

[cam2ski]

Thanks Skniper.

Regarding your shackle question, I don't think I'm seeing what you're seeing, it rides pretty well, I think. which pic are you looking at?

 

[bfoldy]

Very well done. You obviously have some prior experience working with wood, but your write-up lays out the steps well enough that if someone were inclined, they could pull this off.

Question on the two-tone staining process...how did you ensure a crisp line between the two shades? Is it as easy as using masking tape?

 

[OG SUV]

Very nice. Thank you for sharing your build and install

 

[s0me0ldt0ys]

Clean install. Great work. As mentioned the riv nuts do a fine job for holding, and add a good finished look. I like that you kept the two-toned color on the wood finish.

 

[cam2ski]

thanks all.

bfoldy, yeah, just a strip of quality painters tape. I go over it firmly with a dowel or a pen to make sure that it's created a quality adhesion. When applying the stain, try not to come at the tape, try to start right on the tape and then wipe away from it. If that makes sense...

 

[dannyvp]

I’m about to do something very similar to this. I dont know how much I want to spend on hi end speakers though, with a loud truck.

I am looking at the slide out screen radios though.

 

[cruisermatt]

I like this a lot, I’d like to do something similar. One question since I’m an audio novice, does sub mounting need to be in wood for vibration isolation? Do you think a metal panel (with deadened applied on the back) with a wood enclosure for the sub would work decently enough?

 

[dannyvp]

I like this a lot, I’d like to do something similar. One question since I’m an audio novice, does sub mounting need to be in wood for vibration isolation? Do you think a metal panel (with deadened applied on the back) with a wood enclosure for the sub would work decently enough?

Check out this page, tons of great information. How to Build a Subwoofer Box | KICKER®

 

[cam2ski]

I like this a lot, I’d like to do something similar. One question since I’m an audio novice, does sub mounting need to be in wood for vibration isolation? Do you think a metal panel (with deadened applied on the back) with a wood enclosure for the sub would work decently enough?

Are you saying build an enclosure out of both wood and metal panels, or build a complete enclosure out of wood and then mount it to a metal panel and drop the driver through both panels?