[How-To] Subwoofer Upgrade - Replacing/Upgrading the Factory Sub

[RagnarKon]

Just get one of these https://www.amazon.com/Channel-Power-Relay-Module-Control/dp/B0867Z2DXN and use it to trigger remote turn on. Use the existing amp power as the 12V source (common), hook the 6V into the vcc + trigger lines, ground it to your amp ground. Use the Normally Open output as your new 12V accessory wire.

This relay would also work but you'd probably want the Vcc+ line to be rated for a higher voltage since that enable line can float a bit. (I just checked the service manual and Ford considers voltages between 3.5V and 9V to be valid. )

Also have to be careful since that is an AC relay. Granted we're dealing with such low current/voltage it probably would never be an issue... but probably a good idea to buy one that is intended for DC.

Yes, I have one (High pkg so no B&O) . . . and to my knowledge there's no fake DSP. So that's why I was asking.

It's actually just a fake amplifier, not a DSP. All of Ford's wiring diagrams will label it as a DSP though. B&O is the only audio system that has a true DSP.

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[Karl_in_Chicago]

Mine was fake. Here are the pics.

I have the same thing - one is an amplifier and the other is a subwoofer. I thought you were reporting something new - at least to me - that perhaps Ford had introduced a running change of a dummy DSP as well (presumably on the B&O) - which would have been actual news. If you wish to refer to the amp as a DSP then have at it, it's just not how I think of that unit.

 

[jrbreeland]

I have the same thing - one is an amplifier and the other is a subwoofer. I thought you were reporting something new - at least to me - that perhaps Ford had introduced a running change of a dummy DSP as well (presumably on the B&O) - which would have been actual news. If you wish to refer to the amp as a DSP then have at it, it's just not how I think of that unit.

yeah I was wrong. I was going off the wiring diagrams. Fake amp is what I should've said.

 

[BlarneyStoned]

Also have to be careful since that is an AC relay. Granted we're dealing with such low current/voltage it probably would never be an issue... but probably a good idea to buy one that is intended for DC

Yeah the ones I used in my LR3 were actually opto-isolated and DC rated, like these: https://www.amazon.com/HiLetgo-Channel-optocoupler-Support-Trigger/dp/B00LW15A4W/133-0818718-9332011. The opto-isolated ones are more likely to care about VCC voltage range.

There's always the option of using an old school bosch style relay set up like this: https://www.the12volt.com/relays/relaydiagram25.html.

If you don't care about retained accessory power, or the ability to turn the radio on while the car isn't running you can tap one of the ignition-on spare fuses and use that as a remote turn on.

 

[jrbreeland]

Yeah the ones I used in my LR3 were actually opto-isolated and DC rated, like these: https://www.amazon.com/HiLetgo-Channel-optocoupler-Support-Trigger/dp/B00LW15A4W/133-0818718-9332011. The opto-isolated ones are more likely to care about VCC voltage range.

There's always the option of using an old school bosch style relay set up like this: https://www.the12volt.com/relays/relaydiagram25.html.

If you don't care about retained accessory power, or the ability to turn the radio on while the car isn't running you can tap one of the ignition-on spare fuses and use that as a remote turn on.

I actually like the idea of a relay since that will have it working most like a true remote turn on and I can grab one on the way home.

https://shop.advanceautoparts.com/p...OwsVceKB5tdJ341LSYRoCBRoQAvD_BwE&gclsrc=aw.ds

Would this be correct?

85 - ground
86 - 6V turn on
87 - 12V from Kicker amp
30 - remote turn on to Kicker amp

 

[BlarneyStoned]

@jrbreeland Yes that looks correct. The only real caveat is that some bosch style relays won't trigger with just 5-8V on 86 so you might need to try a few different ones till you get one that does, but in my experience most of them do work at lower voltages.

 

[RagnarKon]

I actually like the idea of a relay since that will have it working most like a true remote turn on and I can grab one on the way home.

https://shop.advanceautoparts.com/p...OwsVceKB5tdJ341LSYRoCBRoQAvD_BwE&gclsrc=aw.ds

Would this be correct?

85 - ground
86 - 6V turn on
87 - 12V from Kicker amp
30 - remote turn on to Kicker amp

I have the SPST version of that relay sitting in my junk parts and just measured it—clicks on at 7.6 - 7.9 volts and doesn't really stay permanently on until 8.9 volts.

There is undoubtably going to be some variation between the relays (even of the same model), but yeah. Going back to what @BlarneyStoned said... 6 volts may not be enough to keep it turned on.

 

[jrbreeland]

I have the SPST version of that relay sitting in my junk parts and just measured it—clicks on at 7.6 - 7.9 volts and doesn't really stay permanently on until 8.9 volts.

There is undoubtably going to be some variation between the relays (even of the same model), but yeah. Going back to what @BlarneyStoned said... 6 volts may not be enough to keep it turned on.

Dang. It was so promising. Ok, I'll just tap the power port in the back.

 

[BlarneyStoned]

@jrbreeland There is also a solution from PAC audio if you don't mind spending a few bucks: https://catalog.pac-audio.com/catalog/specialty-items/tr-4

It's specifically designed to turn a low-volt remote signal into a 12V signal.

https://www.amazon.com/PAC-TR-4-Remote-Turn-on-Module/dp/B0002J22BE

Crutchfield has a better price if you're buying any other stuff from them: https://www.crutchfield.com/p_541TR4/PAC-TR-4-Trigger-Module.html

 

[Mudfish]

If you watched my last video you will know that I installed the B&O subwoofer. This time I have upgraded that B&O subwoofer with a Kicker 8" sub!

Check below the video for a TON more information that I've collected.

Other videos/guides I've created on the topic of audio upgrades:

• [How-To] Factory Bronco Speaker Replacement
• [How-To] Amp Install - Kicker Key 200.4
• [How-To] FORScan Audio/Speaker Mods
• [How-To] Subwoofer Upgrade - Trim panel removal & Kicker install

AUDIO SYSTEM VARIANTS

As of now (mid-2023) there are four variants of audio systems in the Bronco. How you add/upgrade your subwoofer will depend on which setup you have.

2021 - 2022MY Six-Speaker
This was the audio system that was included in all non-Lux packaged Broncos. There is NO factory subwoofer, nor is any wiring available to support a subwoofer.

2023MY Seven-Speaker
Included in early 2023MY Broncos. This is identical to the 2021 - 2022MY setup, with the addition of an amplifier and a subwoofer.

2023MY Seven-Speaker with Sub Delete
Ford messed up and ran out of subwoofer components. Functionally the same as the 2021 - 2022MY setup. HOWEVER, it contains the wiring and enclosure necessary to hook up a subwoofer & amplifier.

2021 - 2023 B&O
This is the premium audio system included with the Lux package. There are 7 speakers with a single subwoofer measuring roughly 8" in size (a little less than 8" to be exact).

PICKING YOUR SUBWOOFER

At a high level... there are three decisions you need to make when picking a subwoofer:

• Voice Coil Impedance
• Speaker diameter & depth
• RMS power requirements

In addition those three items, there are other specifications such as frequency response, sensitivity, etc. etc. Most people will not have to worry about these items unless they are really trying to optimize their setups. Given I am gearing this post more towards the novice DIY type... I am going to ignore these items. However, you are free to ask questions about these topics or look online. In addition, if any of you car audio pros feel like there is an important aspect I am ignoring... post in in the comments.

Voice Coil Impedance

You will find that subwoofers intended for car audio generally come in two impedance ratings: 2Ω and 4Ω. There is a lot of electrical and power engineering I could dig into, but just to generalize it:

2Ω voice coils will be much louder and more more "boomy", as they can handle more power flowing through the voice coils. Those who dislike 2Ω voice coils often describe it as sounding very "sloppy", while those that like it often describe the bass as very "full" sounding. If you are driving those 2Ω voice coils with an underpowered amplifier, you run the risk of overheating your amplifier and/or creating very "muddy" sounding bass.

4Ω voice coils will have a more tight and clean sound. Uses less power than 2Ω voice coils, and generally more "safer" for underpowered amplifiers. For this reason... if you are running a factory amplifier rather than aftermarket, I generally recommend sticking with 4Ω voice coils. Those who like the sound of a 4Ω subwoofer would describe it as "accurate" sounding, while someone who dislikes 4Ω voice coils will often say it sounds "constrained".

Speaker Diameter

Generally speaking, the bigger the subwoofer the better. BUT, the bigger the subwoofer the more power and space it will require. Unless you are willing to devote your entire cargo space to a subwoofer, most of us will have to come up with some sort of compromise when it comes to the size of the subwoofer.

If you are mounting your subwoofer in the factory location—in the cargo area passenger side panel—you have two sizes available: 6.75" and 8" subwoofer speakers. BUT, there is aftermarket enclosures available—more on this in the enclosure section.

Obviously your subwoofer will need to be able to physically mount inside of whatever enclosure you select. This will be highly dependent on which enclosure and subwoofer you select, and there is a near-infinite amount of combinations available. The only real advice I can give here is "RTFM and measure before buying".

RMS Power Requirements

Obviously you need to pick an amplifier that is capable of powering your subwoofer. More on that in the next section...

PICKING YOUR AMPLIFIER

There is a TON of amplifiers out there in the marketplace. I definitely encourage you to shop around, and gather suggestions from the forum.

One of the more popular amplifiers is the Kicker Key 500.1, which is the amplifier I personally selected—largely because it was compatible with the Plug-n-Play Kit I bought. My brother—who generally knows more than me about car audio—also suggested the Kicker CX series of amplifiers. In my past I would have highly suggested AudioControl amplifiers, but admittedly I have zero experience with their current product offerings.

Arguably the most important part of any subwoofer amplifier is the amount of power it can deliver at a given impedance rating. It's probably easiest to explain this using an example...

Pretend I have selected the following components:

• Amp: Kicker Key 500.1
• Sub: Kicker Comp RT 48CWRT84

The amplifier I have selected has the following specifications. Notice that the maximum power output of the amplifier depends on the impedance rating of the subwoofer.

The subwoofer has the following specifications. Notice the recommended amplifier power is 300 watts. This is the recommended power output when the subwoofer's voice coils is wired in parallel.

What does this parallel business mean?? Well... there is two ways to wire a dual voice coil subwoofer. If you wire subwoofer in parallel, the impedance rating seen by the amplifier is HALF of the value of the voice coil rating. If you wire the amplifier in series, the impedance is DOUBLE the value of the voice coil rating. A 2Ω subwoofer in parallel will cause the amplifier to see 1Ω of impedance. If that same subwoofer is wired in series, the amplifier will see 4Ω of impedance. Wiring diagrams below:

In this case, our subwoofer has 4Ω voice coils, and when wired in parallel, the impedance seen by the amplifier is 2Ω. The Kicker Key 500.1 is rated for 300 watts and 2Ω impedance, which matches the subwoofer's requirements. So we're good to go.

Modern amplifiers are also typically packed with a ton of added features that you may or may not find helpful. Definitely read user manuals, check out reviews online, etc. etc.

SUBWOOFER ENCLOSURE

General speaking there are three choices for subwoofer enclosures:

• Using a powered subwoofer. This has the amplifier, the subwoofer speaker, and the enclosure in a single unit. The Kicker Hideaway series is a popular example of a powered subwoofer.
• Using an external enclosure. This can be as simple as an standard subwoofer box you stick in your cargo area, an enclosure that mounts to your tailgate—such as the Stinger TXFBB12, or even a DIY box you built yourself.
• Mounting it to the factory location. Three options for this:
  • 2023MY base audio enclosure - 6.75" enclosure
  • B&O enclosure - 8" enclosure
  • Aftermarket enclosure, such as the JL Audio Stealthbox.

Personally, I like the factory location as I value my cargo space, but obviously the choice is yours.

Whichever you decide... check your measurements.

HOW TO WIRE YOUR SUBWOOFER AMPLIFIER

Obviously this will vary widely depending on exactly what gear you purchase. So I am going to speak in extreme generalities. If you need help filling in the gaps, let me know.

POWER

Most people will have to pull their amplifier power from the battery, but the 2023 have the option to pull their power from the factory wiring, assuming they have a relatively low-powered amplifier.

Variant	Power from Battery	Power from Factory Wiring
'21-'22 Six Speaker	Yes	No
'23 Seven Speaker	Yes	Yes, but careful (12 ga. wire)
'23 Seven Speaker (Sub Delete)	Yes	Yes, but careful (12 ga. wire)
'21-'23 B&O	Yes	No

GROUND

Just about everyone will be able to use the ground near the passenger rear cargo area behind the panel. Those with the 2023MY may also use the factory wiring provided, but keep in mind the ground wire should be the same gauge as the power wire or larger (thicker cable).

AUDIO SIGNAL

This is where it gets interesting...

'21-'22 Six Speaker

Those of you in the unlucky 2021-2022 6-speak camp will have to steal their subwoofer amplifier signal from the left and right kick panel speakers. There really is no other way around it. Of course, certain amplifiers and kits made by companies such as @plugnplaykits can make this task substantially easier for you, but fundamentally it all has to come from the kick panels.

Factory Setup

With Subwoofer Upgrade (Proposed)

'23 Seven Speaker / '23 Seven Sub Delete

2023MY Broncos have all of the wiring in place for an amplifier, regardless of whether you have the sub delete option or not. Upgrades are as easy as taking the old amplifier/subwoofer out (or their fake equivalents), and installing the new amplifier and subwoofer.

Note the 2023MY Broncos with the sub delete option will need to use Forscan to turn on the subwoofer output from the ACM. This output will be a low level (aka: line level) output, not a high level (speaker level) output.

Factory Setup

Factory Setup - Sub Delete

With Subwoofer Upgrade (Proposed)

'21-'23 B&O Package

The B&O package makes it tricky. The amplifier in the rear of your Bronco near the subwoofer is not just a simple amplifier. It is an entire digital signal processor (DSP) that also powers more than half of the speakers in your Bronco. That DSP talks to the factory Audio Control Module (ACM) over a digital connection using a protocol called A2B. Therefore you cannot simply replace the DSP with an amplifier.

There are several companies out there that have aftermarket equipment capable talking on the A2B protocol. BUT, if you are simply going for a factory subwoofer upgrade, your amplifier will have to daisy-chain off of the B&O DSP output.

Factory Setup

With Subwoofer Upgrade (Proposed)

MY PERSONAL SETUP

I have a 2022 Bronco with the standard 6-speaker setup. To feed the subwoofer amplifier I am using a Plug-N-Play kit from @plugnplaykits. That kit steals the signal from the front kick panels, passes it through a load resistor to clean up the signal a bit and give the factory ACM something to look at, and passes it back over the wiring hardness to a Kicker Key 500.1.

OTHER THREADS/VIDEOS...

These are thread I've come across that I felt were extremely helpful. If you got one I missed, link it and I'll add it to this list.

Threads

• 2023MY Speaker Upgrade Megathread
• @jshapz - 2023 7 speaker subwoofer upgrade
• @cmcbronco - B&O sub installed on Base Bronco ….sorta….
• @John P. - John’s 2 Door Badlands Build (B&O Replaced with Active DSP)
• @Ksjrb03 - B&O sound system complete upgrade - Done

Videos

• Kicker Hideaway Powered Sub Install
• @1Five1 Garage - Interior Trim Removal and Soundproofing

FACTORY WIRING DIAGRAMS

Hope that was helpful!!!

Thank you for doing this extensive write up. I have read it a couple of times and it still seems to advanced for me personally but I do very much appreciate it. I have also watched your video and it is also great but it also like watching someone you love during major surgery I just want to put a working factory size sub in its proper location......maybe even a hideaway or jbl basspro nano under the rear seat like someone else recently did.

 

[RagnarKon]

Thank you for doing this extensive write up. I have read it a couple of times and it still seems to advanced for me personally but I do very much appreciate it. I have also watched your video and it is also great but it also like watching someone you love during major surgery I just want to put a working factory size sub in its proper location......maybe even a hideaway or jbl basspro nano under the rear seat like someone else recently did.

Definitely check out the link to the 2023MY subwoofer megathread at the bottom of my first post. (I would link it here but I'm on mobile at the moment.)

A lot of people are buying a Ford Fusion amplifier, pairing it with a Kicker 6.75" 4Ω subwoofer, and turning it on with Forscan. You'll still have to remove the rear panel in the cargo area to access everything, but that is as close to "plug-and-play" as you are going to get, and it removes a lot of the complexity. You won't get fantastic results as you are essentially installing a factory-like setup. But it is much simpler overall if aftermarket gear is a little too overwhelming.

If you DO want to dig into the aftermarket gear though... feel free to ask questions here and we can help you get going. Or if it's easier you can just send me a direct message.

 

[Muddog899]

Quick question about the sub box is the base one also ported or only the bo sub box ported

 

[BlarneyStoned]

@Muddog899 both are ported

 

[RagnarKon]

@jrbreeland There is also a solution from PAC audio if you don't mind spending a few bucks: https://catalog.pac-audio.com/catalog/specialty-items/tr-4

It's specifically designed to turn a low-volt remote signal into a 12V signal.

https://www.amazon.com/PAC-TR-4-Remote-Turn-on-Module/dp/B0002J22BE

Crutchfield has a better price if you're buying any other stuff from them: https://www.crutchfield.com/p_541TR4/PAC-TR-4-Trigger-Module.html

This thing seems cool! Just bought two for a completely unrelated project (nothing to do with the Bronco). It doesn’t list an input range, so I’m guessing it’ll accept anything between 0.8V and 12V, But I’ll test it out to see which voltages it accepts when it arrives.

 

[ILoveToDrive]

In my case, yes, the factory audio control still impacts the sub-woofer and the 200.4 sound stage.

The 200.4 creates it's own sound stage, the sub does it's own thing but really enhances the whole thing.

What's your sub setup again?

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