DIY 3.5" JL Audio dash speaker upgrade - Wow!

After seeing a few posts about speaker upgrades, I decided to do one to the dash speakers in my '18 TRD Pro, and thought I'd share. In short, this lower cost, relatively easy upgrade is well worth it, and makes a huge difference in sound quality!

Rather than just going with a popular tweeter upgrade (aka, ), I decided to go with 3.5" coaxial speakers from JL Audio - the C2-350x models. These full range speakers cost ~$80, and I bought mine at Amazon - https://www.amazon.com/dp/B001UDNXOQ





I also purchased a pair of tweeter wiring harness adapters, so I didn't have to cut the factory wiring (others have taken apart the stock speakers to make an adapter plug of sorts, or kind of "jumpered" the male portion of the 4 wire factory plug). I got the adapters from Taco Tunes - To limit lower frequency sounds from being played by these speakers, and prevent "clipping" at higher volumes, I also bought a pair of 133 microfarad capacitors (aka "bass blockers"), to cut sounds below 300 Hz - https://www.amazon.com/dp/B017AJ5ECW



The construction differences between the OEM and JL Audio speakers are notable:





Removal of the stock speakers is easy. I started by using a plastic trim tool (part of a set like the ones at https://www.amazon.com/dp/B00ZRJCYQ2), and gently prying from the center/rear-most portion of the speaker grills to "pop" the two clips that hold them in.



From there, a small ratchet, extension, and 10mm socket was used to remove the two hex head screws (with Phillips patterns in the top, as highlighted in red in the image below). After these screws have been removed, the speaker mount and speaker can be lifted out as an assembly. Push the tab on one side of speaker plug/harness to release it from the blue "cap" of the stock speaker, and disconnect the speaker assembly (the second image below is one where the factory mount is still in place, but I suggest removing the speaker and bracket as an assemblly, vis the Phillips head screws)





The Taco Tunes adapter harnesses make wiring a pretty simple affair. Because of the way that the door speakers are wired with the dash speakers, there are four wires in the factory dash speaker harness/plug. To mimic the same using the Taco Tunes adapter harnesses, make four wires into two -- red and white wires go together for the positive side, and black and white/black go together for the negative side. I cut the long wires of the Taco Tunes adapter harnesses down to about six inches, to reduce bulk when installed under the dash.

The capacitor is connected inline, on the positive side wire. Joints were soldered and finished with heat shrink tubing.





Next, I fabricated some mounting tabs out of 1" wide x 1/8" thick aluminum bar stock, which can be purchased at most hardware or home improvement stores. These didn't have to have as complex of a shape as I made them, and a simple rectangle would have worked, but mine are shaped like they are due to earlier plans changing a bit, and not wanting to re-make the brackets.

Rectangular tabs would be 1.75" long and .75" wide. Two holes are drilled in the tab, 1 5/16" apart. The smaller one at the top (which the Phillips head screw will go into) was drilled using a 5/32" bit, and the larger one was drilled with a 3/16" bit.

The hardware used to attach the tabs to the speakers is 8-32 button head machine screws that are 3/4" long, with matching nuts and washers. I put one washer under the screw head, two washers between the aluminum tab and speaker (for spacing), and one washer under the aluminum tab.



The Phillips head screw can be used to make threads in the smaller/top hole. It takes a little force to start the screw in the hole, but do this, tighten until snug, and then remove the screw. It is much easier to do this outside of the vehicle, than inside when mounting the tab/speakers in the dash.



This photo depicts what the tab looks like when mounted on the speaker. The Phillips screw was removed prior to putting the speaker in the dash. I put blue thread locker (aka Loctite) on the button head hardware, and tightened it fairly well, but just loose enough so that I could move/align the tab with the speaker in the dash hole.



When installing the speakers in the dash, the side of the speaker without the "tab" attached will be fastened using the Phillips head screw and existing "spring nut" that is already installed on the dash plastic. On the opposite side, you'll need to remove the "spring nut" by simply sliding it off the dash plastic (don't drop it into the dash hole, or it may be hard to retrieve. The photo below shows one of the spring nuts after it has been removed.



After plugging the factory speaker wiring harness to the speaker, and tucking in the wires, the speaker can be carefully dropped into the dash hole. On the driver's side, put the speaker "ear" on top of the spring nut that is on the left, and loosely fasten it with one of the Phillips head screws. The fabricated "tab" on the other side of the speaker goes under the dash plastic where the spring nut previously was. Insert the Phillips screw through the top of the dash, and tighten it into the tab below, as depicted in the images below. Don't overtighten the Phillips screws on either side of the speaker, and it is a good idea to put some thread locker on them.

The installation of the passenger side speaker is similar, but it is a tighter fit due to the ductwork for the defroster vent below the speaker hole. It took some wiggling and pushing down to get the speaker into position, and clearing the sheet metal closest to the windshield.





The OEM speaker grills have a ring on the bottom side that meets up with foam that is on top of the factory dash speakers. I used an angle grinder and sanding disc to carefully sand away/remove both rings, so that the back of the grills was essentially flat, and no speaker interference would occur.





Snap the speaker grills back into place, and the installation is done.

Now crank up some tunes, and enjoy the much improved sounds, as well as the satisfaction that you did it yourself!!

 

Great write up, I need to get going on my upgrade.

 

Did the same buy used JBL GTO series 3.5" coax speakers. The Subi tweeter upgrade is a total waste of money, still just a tweeter. This is absolutely the way to go. I removed and reused the OEM tweeter plugs, bypassed the OEM capacitor, soldered it all together and good to go. Still plug and play, no cutting of the OEM wiring, saves the 30 bucks or so on the tacotunes adaptor harness.

 

anybody in San Diego, CA know a place to get this done? or is there a better upgrade option to get better sound without taking away any storage area? With 2 young babies, no time for a DIY project. Thanks in advance for any recommendations.

 

Wish you were in AZ, I'd help you in a second.

 

Jen
Try diy..it's easier then you think,follow the instructions per the thread above. The only time consuming part is removing the old connector from stock tweeter, soldering the cap to block bass from midbass. I will probably do mine in 2 weeks.

 

YES
If you want I can walk you thru after I do mine.....I will ping u after I am done or if you decide to do it before, let me know...we can chat or text

 

Which ones would have better sound quality? JL Audio - the C2-350x or JBL GTO series 3.5" coax speakers?

 

Doubt you'd notice the difference between the 2 being such a small speaker. JL speakers are an easier install since the JBL speakers have a tall plastic lip around the edge that has to be trimmed in order to clear the grill. JBL speakers will last longer being a rubber surround rather than the foam surround on the JL speakers which will deteriorate quickly being directly in the sunlight.

 

Just ordered JBL 3.5" speaker suggested by Chris above.....I will try to keep factory harness by prying it out.....Will update once speaker arrives and installation is complete......

 

If you need assistance just let me know!

 

Speakers arrived yesterday and I decided to stay up to do it......JBL GTO 329 are not bad.....Only hang up was the passenger side's tight fit.....There are a couple ways to mount the speaker on my install, cut the stock mounting adapter or use speaker brace some use to secure a sub box. The plastic speaker grill will need a dremel job to accommodate the height of the JBL's.
Sound is definitely an upgrade, now I want to add all new Door speakers and 4 channel Amp.

 

Shave down the plastic ring around the edge of the JBL speakers, they will fit much better. I added the JBL GTO 6x9s to the front doors which was also a big improvement. For me this is all temporary so I haven't bothered to amp them. Ultimately I will have a 5 channel, 6 channel, active system but I needed something to hold me over.

 

Chris,
Thx for the tip of reusing the stock speaker harness....Saves time, $, and keeping it stock!

 

I thought about what you brought up but wanted to trim the cover ring first to see if it will fit....Snug but fits.....

 

You're welcome. You do have the polarity wrong though. Cap goes on the positive side of the speaker which it looks like you've got right. Your positive wire is soldered tot he negative terminal on the stock plug though. Positive side is where the OEM cap is. Also make sure you bypass that OEM cap otherwise all you'll get is very high frequencies out of your new speakers. Look at this picture for reference.

 

Hmmmmm, on the stock harness, I could not tell where positive or negative is so solder positive on white stock wire, negative on black side......Am I reverse on that?

 

Yes. If you look at mine, the white/black wire is negative, solid white is positive. Also desolder the stock capacitor and remove the terminal to take that out of the equation.

 

I can just disconnect stock cap or pull it out and plug will still work right?

 

Yep I left mine there just because I didn't feel like pulling it off but it is disconnected. If yours is still connected, your new dash speakers are getting the same high frequencies your stock tweeters did. Remove that cap, reverse the polarity so it's correct, take a listen. You like it now, just wait till you hear it when wired correctly. You can also run much thinner wire if that wire is getting in your way. Looks like 12 gauge, definitely overkill but won't hurt anything if that's all you have around.

 

I just purchaced the JBL GTO speakers and noticed they come with 150 microfarad capacitors. I notice you used 133 microfarad capacitorssetup with the JL speakers. Is there an enough of a difference to use one over the other?

 

There's a formula you can use to determine what frequencies get blocked based on the caps and impedence. If the JBLs came with 150 microfarad caps, you should be fine and it'll sound great.

 

The JBL speakers are 3 ohms, the JL speakers are 4 ohms. This changes how the capacitor works. Use what came with them, JBL knows what they're doing.

 

Yeah my JBL club 3020 came with 270 uf, caps, I didn't notice them until I flipped the foam packaging to throw the box away when I was done soldering 14uf to the speakers. I'm going to run the 14uf for now and maybe test one 270uf and adjust left and right balance to see if I notice a difference

 

The fact that the door speakers are wired in parallel with the dash speakers and resistance of all speakers should be taken into account when calculating what capacitors to use. Pretty good, related read at https://www.hometoys.com/article/2002/06/series--parallel-speaker-wiring/1775/

 

The cap does not see the door speaker, it only sees the 3.5 so what's in the door means absolutely nothing. If the cap saw the door speaker, the cap would act as a crossover on that speaker as well. Use what they came with. Trust me, you don't know better than the company that supplied the cap and has to warranty the speakers. I went with the GTO series which came with a 150UF cap which I used and they sound great.

 

Re-read my last post, as well as the one from me above it. Caps will be affected differently, depending on the impedance, which varies based on wiring type (series versus parallel).

 

Thanks for your reply Eric. I agree, the JBLs came with the 150 microfarad caps for a reason. I'll let you know how it turns out.

 

Does anyone have a suggestion for a replacement for the door speakers that would go well with the JBLs in the dash?

 

Focal has a setup for the runners. I do not have a link for you though. Power Bass also makes some for our rides. You can see them at Crutchfield.