Stereo Overhaul - Mild Documentation

[gringoloco]

The BM-11 is quite interesting. I provided a little 3d modeling design help to Nick for the BM-MKV. The S-surround design is really neat.

I need to get the Stealthbox in hand to get some measurements before making any decisions. It might be possible to add a mounting ring/spacer to increase the mounting depth. Or even widen it to accommodate a larger diameter driver. But it's all guesses until I can see it.

I wouldn't mind butchering the trim panel a bit if necessary. It's not a show car after all.

Do we know the volume of the Stealthbox for certain? I might have read .3 cu ft, but since they don't even have a product page for it yet, I'm not certain.

I've got zero regrets about the SI 3-ways. Been on a road trip the last few days making our way home and have logged a bunch of listening time. It sounds incredible.

I’m guessing the enclosure is in the neighborhood of .3-.4 cubes, based on the other options on the market that advertise their volume.

Thanks for the updates, helps keep me motivated. Getting my last few items together for my full SI/Helix install, build thread will follow soon.

Did you have to cut much dashboard for the components to fit?

Sponsored

 

[brtd]

Did you have to cut much dashboard for the components to fit?

I just looked and somehow I neglected to take pictures after trimming the material. I'll grab a snap or two if I ever pull one out.

I had to remove a lot of plastic. Enough that it was a challenge to leave enough material to properly support the slots that receive the clips that hold it in (my mounting installs into the clips that hold the stock grill).

It worked out okay, but it was not my favorite part of the project. Flush cutters, oscillating tool and vacuum to minimize the mess.

I also had to grind away portions of the acrylic "sandwich" that holds the drivers, including some of the screw heads that held the assembly together. I supplemented with glue. It all worked out in the end, but hardly a plug and play setup.

Would have been far easier to sink the midrange and do a pod for the tweeter, but I find those to be distracting on the dash and I didn't want to mess with the A pillar and airbags, though I've seen others on this forum who nailed it with that location.

Here's a before picture with the red line approximating the removed material.

 

[mObridge]

Hi all,

What a build...

Happy to answer any questions regarding the amplifier or DSP!

We now have a completed kit for this amp that comes with all harnesses and bits needed to install into a Bronco so you don't have to go through the same pain as @brtd!

https://mobridge.us/product/mobridge-bo-a2b-ford-bronco-amp-pnp/

Cheers,

Fraser

 

[brtd]

Got my JL Stealthbox a few days ago.

Here's how it compares to the stock BO sub.

Some dimensions for anyone curious about fitting another driver in here.

Pretty minimal stuffing for a sealed enclosure. I added some additional polyfil.

I think the stock enclosure did a better job of using the space available in the cavity. The JL is leaving a lot of space on the table in my opinion.

My understanding is that this enclosure has about 0.35 ft^3, which is what they spec for the 10TW1. But they could've easily found another .15 ft to spec it for the 10TW3.

Not saying it isn't good. It clearly outperforms the BO sub in every way. I'm just not certain yet if it is enough for my taste.

I currently have a limiter on the sub channel to keep it around 400watts. If I replaced the driver with the Tw3, I could remove that and feed it 500 watts. In this small enclosure, it would be near impossible to push it beyond xmax, whereas even 350 watts with the TW1 at 40hz reaches its 10mm xmax in simulation.

Here is how 400 watts with the TW1 compares to 500 watts to the TW2 in the stealthbox enclosure. It's about a 3db improvement.

Still need to EQ and level match the TW1 before I make any decisions.

 

[kcbronco]

Got my JL Stealthbox a few days ago.

Here's how it compares to the stock BO sub.

BRTD did you find the grille template that the directions mention. Also did you have any trouble getting your inside quarter panel back over the subwoofer. I looked everywhere and cannot find the template. I'm also having some trouble getting the panel back in. It almost seems like it should go down a bit but there is a big chuck of sound deadening materiel on the wheel well were the box sits.

 

[brtd]

@kcbronco I do have the template. I will scan and upload it here today unless it's too big to scan.

I'm swapping the driver for a 10TW3 (arrives today). Once that is done, I'll work towards reinstalling the panel. I did a quick test fit yesterday without snapping anything in... Gonna be tight, but I think it'll work. I'll report back

 

[skibumbrian]

Hi all,

What a build...

Happy to answer any questions regarding the amplifier or DSP!

We now have a completed kit for this amp that comes with all harnesses and bits needed to install into a Bronco so you don't have to go through the same pain as @brtd!

https://mobridge.us/product/mobridge-bo-a2b-ford-bronco-amp-pnp/

Cheers,

Fraser

@mObridge
Hi Fraser,
Do you have a plug & plus kit for non-B/O systems?

thanks

 

[Karl_in_Chicago]

@kcbronco I do have the template. I will scan and upload it here today unless it's too big to scan.

I'm swapping the driver for a 10TW3 (arrives today). Once that is done, I'll work towards reinstalling the panel. I did a quick test fit yesterday without snapping anything in... Gonna be tight, but I think it'll work. I'll report back

Wow, that's going to be really tight. I'dathunk that if the TW3 fit then JLA would have gone with that from the get-go vs the TW1 (or made it an option). Interested to see your results.

 

[brtd]

@Karl_in_Chicago

When I wrote that it was going to be tight, I was more referring to the right rear interior panel.

I was bone-headed and didn't really research the difference in size between the TW1 and the TW3

The TW3 does not fit in the Stealthbox enclosure, as I've learned today. Funny... It's actually shallower. But the basket design is different and requires a slightly larger opening.

 

[Danny's Bronco]

Doing a really great job dude! I'm digging it,

I am wondering when you add the dynamat to the door how does the inner door skin or door card fit back on? Is there gaps or anything noticeable?

Finally getting my 2dr after a 3yr wait. I think I might skip adding a kicker to the factory box and buy the stealthbox. I've never used dynamat like that. Just inside a trunk as a teen. I think I am going to watch a little YouTube and see if I can learn how to put that on myself. Just gotta get my Bronco out of the paint shop

 

[brkdncr]

I have a 10w3 in my garage from a different stealthbox and really wished it would fit. It’s a good piece of equipment.

 

[kcbronco]

@kcbronco I do have the template. I will scan and upload it here today unless it's too big to scan.

I'm swapping the driver for a 10TW3 (arrives today). Once that is done, I'll work towards reinstalling the panel. I did a quick test fit yesterday without snapping anything in... Gonna be tight, but I think it'll work. I'll report back

I got it figured out thank you though. it is tight though. On mine I ended pulling the insulation type sheet off the inside of the plastic quarter panel and bending the bracket that goes on top center some to get it to push farther into the fender.

 

[brtd]

Good. I ended up shredding the template a bit when I was taping it to the panel. Wouldn't have printed on letter sized paper anyway. I'm not sure they even scaled it properly tbh. A couple of the holes in the template landed in the existing opening. Oh well.

I got it figured out thank you though.

 

[gringoloco]

Stereo Integrity is working on a 10”, not sure if it will fit, maybe worth a look. Also, check out the audiomobile evo 2410, I think it may be right up your alley:

 

[brtd]

After spending some time with the Stealthbox, I decided it wasn't going to cut it. I am keeping it in place, but it will be sitting idle unless we are roadtripping or camping and need all of the trunk space.

One sub in the trunk for most of the year. I chose a Hertz MP 300. It's a dual 4ohm 12". I heard this same sub powered by the Mobridge amp in Fraser's car this summer. I was very impressed.

This will be connected via a Neutrik Speakon connector. Connects securely and disconnects easily. I will have another mounting plate on the rear interior panel that is wired to the Stealthbox. When I need to switch subs, I just move the cable and apply the appropriate DSP tune from the head unit. One tune for the Stealthbox and three I can use with the Hertz sub (for various levels of sub output). Between the two subs, the EQ filters are a little different, the delays are slightly different, and I have some limiting on the sub channel for the JL.

The goal was to maximize enclosure volume (a touch over 1 cubic foot), while minimizing the loss of cargo space. The raised bump behind the rear seats meant an off the shelf slanted box wasn't going to work. Here's what I came up with:

The triangular space behind the sub was just enough for a right angle speakon connector (after recessing the mounting place a bit). I changed the H and W ratio a bit after taking the screenshot above. The final product is a little narrower and taller.

I did not get the angle right on the first try for the upper rear section, so I had to make a change on the fly.

I used 10-32 bolts with threaded inserts recessed into the double baffle. MDF is not a great medium for screws, especially if you have to take them out more than once or twice.

I used wood glue (with brad nails and clamping) for everything except the baffle. I used PL Premium for the final piece. Great stuff, long working time, expands a bit to fill gaps, and machines or scrapes away pretty easily. Just don't get it on yourself... takes ages to get off your skin.

The shape of the box made the final clamping setup a challenge, so a little jig was necessary.

I've never carpeted a sub enclosure before. I think it turned out pretty nice. My wife helped a lot and we watched some youtube videos to get some tips. Parts express for the carpet, 3M Super 77 for the adhesive.

Here's the Speakon connector. It twist-locks into place and exist the tunnel near the amp.

Overall impressions: It is exactly what I was hoping it would be. It sounds as impressive as it models in simulation vs the JL. About 9db in the region that matters. This is with 500w to the Hertz and 400w to the JL.

It now sounds the way I was hoping it would when I started this project. I always knew the sub was going to be the weak spot. I'm glad I didn't settle. And it'll still sounds pretty damn good when the big sub is removed. 10/10 would repeat.

Sponsored