3rd Gen JBL Subwoofer Upgrade

Alright, so I reluctantly got my Tacoma with the premium and technology package for the extra bells and whistles (I'm pretty much blind in my right eye so I liked the idea of blind spot mirrors and the rear cross-traffic sensors). This package came with the JBL system, which I knew was a pain in the ass to integrate aftermarket upgrades, but I opted for the additional safety features. I did my research and reached out to several vendors like *********, OEMaudio+, etc. to see what my options were. They were clueless about the JBL systems. There were a few guys on here that were smart and technical enough to add an LC7i or other LOC but the amount of wiring required went way over my head. I started to lose hope but thanks to the numerous knowledgeable members of this forum offering their advice and techniques to work around the stock amp, I started to piece together and plan out my build.

Since there are plenty of how-to threads on this topic, this is more of a show and tell that hopefully gives you some ideas/inspiration and makes the process much easier for you. I have very little experience with car audio, let alone with all the intricate wiring, so I learned a lot on the way and figured it out as I went. I didn't think about making a full thread until about halfway through so I only took a few pics here and there as references just for me, but I hope you guys enjoy my first audio build.

The most essential piece of this JBL puzzle was the PAC AMPpro. I can't thank @MannyTheAudioGuy enough for recommending this part and kicking my ass into gear to get this build going. It simplifies the entire install and gives you 6 pre-amp outputs to add on aftermarket parts to the stock amplified system. I forgot to take pics but it's the simplest plug and play harness you could ask for. Just hook everything together, plug in the RCAs and remote sub knob and then toss the radio back in.






JBL's pathetic excuse for a "subwoofer"


I started with the sound deadening on the back wall. Went with RAAMaudio based on price point and plenty of solid reviews on TW. Package #1 was plenty for the rear wall, all 4 doors, and a little under the dash and center console. Huge improvement in road noise and exhaust tone




Got the rear window motor as best as I could and ran a bead of silicone around the black vents to seal everything and keep them from rattling


Not too pretty cuz I made the mistake of trying to do the entire rear wall with a single full sheet, but it's all covered up anyway


First test fit of the box started to give me hope. The enclosure was the first big obstacle working around the power rear window but I got a good price on a custom box from a local shop


Finally moving on to the doors. I didn't take a lot of pictures here but there's plenty of good write-ups that describe this process in detail. I was thinking of replacing the door speakers as well, but after the sound deadening the woofers came to life and all the plastic rattles disappeared. I guess the stock speakers can stay in for now




Little side tip: wrapping all these plastic panel connectors in felt/tesa tape made a big difference and using the panel tool speeds the process up and saves your fingers as there are tons of them








Now on to rerouting the stock amp wiring harness. I had to extend 2 wires that went up toward the 3rd brake light










Made a new bracket out of 1/8" ABS for the stock amp to keep out debris and mount it to the cubby




Just enough room in the cubby


Now on to the wiring... This was my first time soldering so don't judge me haha




Little bit of poly-fil for the small enclosure. The toughest part was bolting the box to the rear wall but now it's in there for good


Subs finally wired up and mounted




There's a grommet right under the driver's seat that made for a perfect grounding point to the frame. Hit it with a quick rust-proof bed liner to cover the bare metal then put a dab of dielectric grease on top just to be safe


Made a little fuse mount that attaches under the fuse box to keep everything accessible


Amp all tuned up and ready to go. I followed someones advice and glued a few wood cutouts to the floorboard and screwed into the wood rather than through the sheet metal


Being a class AB amp and especially since I was bridging the 2 channels, I threw a couple rubber spacers under each screw to help with airflow




Since the back part of the seat was touching the amp and preventing the seat from sliding all the way forward, I kind of stole @olecoot 's idea and added some spacer washers for about a 3/4" lift. I wish I could have gone with his product but with the sunroof, I was already pushing for space between the headliner. This simple little seat mod has already made a huge difference with back pain on longer drives and definitely helps see over the hood scoop. I highly recommend looking into it if you haven't done it already. https://www.tacomaworld.com/threads/fs-aluminum-seat-spacers-for-seat-mod.563843/


I was a little pressed for space between the sub and the rear seat but then I remembered @Man of Steel TRD 's insanely detailed build thread where he used another spacer to push the bottom of the seat forward. Made a huge difference and gives me peace of mind without a grill over the sub


Just don't use more than a 3/8" spacer or the seat bottom won't open/close




Lastly, I mounted the sub volume knob right underneath the armrest to adjust the bass as need be. If you made it this far thanks for reading and let me know what you think the next upgrade should be. Thanks again to everyone on here for all the suggestions and inspiration!

 

Glad that amppro helped you out! Your pics don’t show yet but can’t wait to see the finished project nice write up btw!

 

Yeah, no images besides the bass knob at the end.

I'm so glad you were told about the AMPpro! Such a great piece of hardware for those with amplified stock setups (both Toyota and most other brands)

I've been using them like crazy in my shop (lot's of GM vehicles with Bose and Ford's with Sony systems)

 

Dang no pics are showing up? That was the whole point of this thread haha let me see where I screwed up

 

Are all the pictures showing up on your end now?

 

Wow clean install

 

Yep all good! Nice job!

 

I appreciate it. Not bad for a 23 year old with basically no experience haha

 

Thanks for sharing this! I’ve been wanting to replace my sub and speakers but haven’t been able to find out how to do so with this dang JBL amp while still keeping the stock HU.

Seems like the AmpPro is the missing piece for me.

 

Not to hijack your thread but after looking into the AMPpro, I’m questioning if I really need that whole kit or if there’s another solution that is equally as simple.

What I’m trying to do is remove the stock sub to regain that storage space behind the seat. Run a self contained sub under the passenger seat, and a small 4 channel amp like this (Alpine KTP-445U 4-channel Power Pack Amplifier https://www.amazon.com/dp/B003VVYL46/ref=cm_sw_r_cp_api_Z00WBb6PWH8DZ) along with all new speakers.

I’m very technically savvy and have done a dozen full audio installs but never on an OE amplified system when retaining the OE HU.

 

You for sure don’t “need” the amppro but it wil absolutely get you the cleanest audio signal.
You can use the hi-level output from the jbl amp and run a power pack or similar from that. It will absolutely work. But it won’t work well.
The jbl amp has 7 outputs. Front tweeter x2, front woofer x2, rear speaker x2, and sub x1.
You will need a summing device to combine the front tweeter and woofer signals from the jbl amp so you can use this as your mid/high range front input to the power pack. It will still be a hi/low level converter so this will create some signal degradation.

Or, avoid all that and get an amppro that gives you true full range front/rear/sub pre-amp outputs. Use these outputs to hook up whatever amp you want, and whatever sub you want. I prefer the Kicker Key over the alpine power pack, but have used both many times.

 

Kudos to you for going through the pain of keeping oem amps. I was faced with that on my runnner and ended up just scrapping everything and running an aftermarket deck. Nice install all around, lots of nice little details

Also, I’m not a pro installer by any means, but that main fuse should be in the engine bay, close to the battery imo

 

If it wasn't a brand new truck I would have just started over from scratch and replaced the head unit and probably saved myself a lot of headaches. But since I already spent the extra money on the JBL head unit and amp, I might as well get some good use out of them for a few more years. And the close up picture doesn't show an accurate location of the fuse block, I made the little ABS bracket to keep it close to the positive terminal

 

Oh ya, I see how it is now. For some reason I thought the first pic showed it mounted under the steering column lol. I was like uhhhh I’m not sure that’s right....

 

Hahah yeah that wouldn't be ideal. The first pic is hard to tell where it's at

 

Can you just replace the stock sub with a quality one or is the amp not powerful enough?

 

Was just thinking the same thing. Interested now. I’ll definitely put sound deadening on that rear wall. That will make a huge difference

 

Some people have had luck replacing the JBL sub with another shallow mount but you'll definitely need an aftermarket amp to make it worth it. Honestly, that stock, plastic enclosure is garbage and limits most of the lower sub frequencies anyway so I suggest throwing the sub in a true, solid enclosure.

Sound deadening the rear wall made a dramatic difference in road noise and keeps the sound in the cab much better, but the front doors were the most important to eliminate vibrations/rattles and helps with the hollow sound you get from the front stage

 

Might have to stick with this garbage sub then. Taco tunes sells a plug and play harness for non jbl but seems like jbl ones are a pain in the ass to get working

 

There’s always the under the seat solo subs with built in amp