2024 (3rd Gen) / Non Hybrid / JBL Audio - Upgrade thread

Hello Everyone, **Sorry for the long post, but I think it could be great value

I've searched this forum, and it appears there isn't a dedicated thread for 3rd/non-hybrid/JBL Systems.

I'm aware there are many enthusiasts out there who find the subwoofer and factory amp configuration quite underwhelming. I've posted in the Audio section, but it seems to receive less attention than this one.

I'll begin with my questions, and we can delve deeper as the discussion progresses.

Goal: To enhance the truck's sound quality, particularly the bass, which is significantly lacking.

Here's what we already know:

• You can use a wiring harness for adding a subwoofer to 2018 and newer Toyota models, specifically for speaker signals, available at: https://www.autoharnesshouse.com/82193_info.html
• A commonly used Line Output Converter (LOC) is the lc2i.
• The majority of the frequency output in the truck is directed to the front speakers.

Common Vendors:

• T@coTunes (https://*********.com/)
• https://ground-shaker.com/
• Shop (tech12volts.com)
• Exclusive Dual 10" Sealed Subwoofer Enclosure Package for 22-Up Toyota (ds18.com)
• SBX-T-TCMAX3G/10TW3 - Car Audio - Stealthbox - Toyota - JL Audio

Questions:

1. Given that our trucks come with the factory JBL subwoofer, it seems feasible to connect our Line Output Converter (LOC) to these wires. However, I haven't determined if it's the correct frequency. Has anyone experienced issues with this?

(pulled these pictures from a thread I found)



2. Instead of tapping into the subwoofer speaker output, have you found better control with using the wiring harness that auto house supplies?
a. (My goal) turn bass almost completely off on the display, but push/control all bass to the aftermarket amp/sub.

3. Is there a place to source 12v power from the rear of the truck, or do we need to run two power wires (LOC & Amp) from the battery?

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Answering these questions should assist many people. Now, let's discuss subwoofer placement and amplifier selection.

There is a variety of choices in this category, provided you're willing to sacrifice some storage space beneath the seat, with options including 8-12" subwoofers.

Due to space constraints, what's not commonly available are behind-the-seat boxes or sub configurations.

It would be great for others to share their selections and the reasons behind their choices.

 

Just get this

https://tinyurl.com/3m9r2xte

 

I've heard mix reviews about T@co tunes, not sure why -- But I have looked into this and like the plug-in-play option.

 

Id be ok just getting a harness...I'd trust them with that. The LC2i is a stout lil unit and should be trouble free. I had one for a few years and it worked great, loved the GTO feature.

 

I don't have a 3rd gen but can shed some general insights to your questions that will apply.

1. In this or any vehicle with a factory subwoofer you can tap signal at the factory subwoofer plug with a few considerations. A line output converter is only necessary in this scenario if 1) your aftermarket amp doesn't accept high level/speaker level inputs or 2) you're specifically getting an "active" LOC like an AudioControl LOC with Accubass. If your aftermarket amp accepts high level inputs (most new amps do) an LOC isn't necessary unless again, you're wanting to utilize the Accubass feature. A passive LOC would be unnecessary in this scenario as passive LOC's don't have any signal processing. The downside to tapping into signal at the sub location/end of the signal chain is that the signal has the highest likelihood of being processed. Idk if anyone's measured the signal at various points, e.g. directly behind head unit/pre amp, or post-amp so it's hard to say where factory tuning is implemented (head unit doing vs. amp) but regardless tapping into signal pre-amp will theoretically be a better signal and more likelihood of a full range signal. I believe the AutoHarnessHouse harness plugs in behind the head unit and allows you to splice into one of the FR, FL, RR, RL channels. If one of these channels is full range, then it would also negate the need for a LOC with Accubass or a DSP. Other options include getting a DSP in addition to an amp, or a DSP amp. Some DSP amps will auto-correct factory EQ, like the Kicker Key amps. Other DSP amps will have DSP tuning software.

2. I'd recommend getting a bass knob for your aftermarket amp. You can leave your bass flat on the head unit, but then have your amp gain set to the max safe level. Use the bass knob to turn the gain up/down on the amp and increase/decrease sub/bass output independent of the rest of the system.

3. Almost always need to run a dedicated power wire for an aftermarket amp (unless it's a very small output amp like an Alpine Power Pack, but even then, it's usually recommended to run an 8, 10, or 12 gauge power and ground wire). Line output converters do not consume much power. Easiest thing to do is run an adequate gauge wire for your aftermarket amp, and then use either a distribution block that accepts small gauge wires, or pig tail off your amps 12v+ terminal and run a small gauge power wire to the LOC with an in-line fuse. Audiocontrol recommends a 1 amp fuse.

Couple of options for behind the seat boxes to keep space under the seats available:

2022+ NON HYBRID Toyota Tundra Crew Max 2-10" vented sub box v2 – FOX ACOUSTICS

2022+ Toyota Tundra Single 10 inch Subwoofer Box - Taco Tunes - Toyota Audio Solutions

 

I really appreciate the detailed input; I'm playing devil's advocate a bit with this post. Everything you've mentioned makes complete sense and informs others of the options available to them. From the research I've found our truck do have bass roll-off, so having the Accubass feature is a bonus for the overall sound.

Edit* -- The boxes you listed are great.

Trying to see the depth measurements to make sure the sub selection is correct.

 

I'll also anecdotally add that in my wife's car I have an

$124 AudioControl LC7i Audio Control 6 Channel Line Output Converter with AccuBASS

AudioControl LC7i (leftover from a previous install) that I'm using only 2 channels of solely for the Accubass feature to feed into a mono-sub amp. Wife's car is a Mazda CX-5 with Bose and to be fully honest, I have never gotten the bass to sound right. I've played around with it a ton trying to tune it but I've never gotten it to sound right. That might be specific to that car but I'm not super impressed by the Accubass feature. That shouldn't turn anyone off AudioControl stuff as they make great products. I have a Dayton DSP I might throw in to tune things, but I'm also very on the fence and leaning more towards getting the Kicker Key mono amp as it has auto-DSP that essentially tunes everything for you at the click of a button and would save me a lot of time tinkering with the DSP (and potentially having a lot of noise etc. as the Dayton DSP's have pretty poor quality control from the sounds of it).

 

Looking at the Fox box, not sure how they want you to use dual 10s on that size ported box. Subs call for more cu ft each

 

I don't like that the Fox box requires you to move the seat belt and created a custom bracket. That will void any warranty for sure.

 

I've moved entire benches and seat belts forward but on trucks out of warranty.

 

JL 10Tw3's call for .6 ft^3 but yeah most shallow subs call for around 1 ft^3 of volume per driver in a ported enclosure. Just have to find subs with low ported volume requirements. Even the Sundown's they recommend call for 1-1.25 ft^3. Not sto say you can't put a sub in an undersized enclosure, it'll just stifle them.

I didn't notice that when I quickly looked at it, very solid point. I wouldn't be comfortable moving the seat belt either.

 

I had this big ol thing for a single 12". No way I would trust that Fox builder if he is recommending something that is out of spec. The TT box seems like a better option but also only offers 1.1cu ft. Makes me just want to plug the port and run dual 10s sealed

 

Yeah, moving the seatbelt doesn't seem like the right move just to add a sub in your truck/car. 1.1cu ft. is just not really enough to make it worth it. There is a thread saying it's actually smaller. I'm still leaning towards the JL, unless there is another option that comes up.

 

So, @Bigbeckster, based on how you titled your thread, I'm hoping it's OK if I add my thoughts, pictures and audio "build" in here versus starting another thread of my own.
If not, let me know, no worries. I'm not easily offended.
I DO have a tendency to get wordy....you've been warned.

I think we're heading down a similar audio path, not identical, but similar.
It sounds like you're looking for a ready-made sub enclosure solution.
I'm going the DIY route. Otherwise, the end goal remains the same: (much?) improved sound from our 3rd gen JBL systems.

Disclaimer before I go any further: I make no claims of being ANY kind of audio guru.
I've installed my fair share of car audio over the years. Nothing fancy. No DSP, no time alignment, nothing requiring an oscilloscope and an advanced degree. Built several of my own sub enclosures over the decades, all from 3/4" MDF, and all sealed enclosures, not ported. Never dove in with fiberglass. So....simple, I guess. But I try to live by the KISS principle, and did I mention I'm cheap?
I'm just a middle-aged guy that still likes his rock and roll on the louder side and thinks that the JBL system is lacking in a couple key areas. Despite the "louder" reference, I'm not into window distorting bass. I'd like to think I'm more of a SQ guy.

 

Yes, we're on the same page -- I worked at an audio shop for about 3 years right after high school, so I've done my fair share of installations. I've dabbled in box construction, but it's quite a science to get the sound right, and I don't want to invest the time. Moreover, the limited space behind the seats in a non-hybrid vehicle is already a challenge.

That's precisely why I'm considering the JL prefab box. I'm not keen on giving up the storage space, especially since it was one of my main reasons for choosing a non-hybrid model initially.

 

I'm right there with you right up to the JL Audio stealth box. I'm sure it's a fine piece, but it's too rich for my blood.
I seriously considered some of the other better all-in-one space saver type sub/amp combos, but ultimately I wanted more flexibility and ability to upgrade other speakers in the future using a multi-channel amp.

I was going to address your original questions, but @Snert covered everything thoroughly.
A couple thoughts on LOC's with bass restoration. (Audio Control's Accubass and similar. I'll be using a LC7i also.)
To my way of thinking it doesn't make sense to utilize the JBL sub leads for inputs if we KNOW that there are frequency and/or level shenanigans going on with that signal.
I'd rather pull full-range speaker signal from the front door leads (or sum signals as needed) and skip the Accubass.

 

I agree. How do you plan to manage pulling from the front door leads? I've reached out to T@coTunes for clarification on this because if they can connect the LOC using the leads from the front off the factory amp, it could be quite beneficial. I prefer the neat appearance of wire harness if it's necessary to interfere with any leads.

 

Using either the Taco Tunes or Auto Harness House jumpers at the JBL amp under the seat.

 

Do we know its the amp that is performing the roll off? Because if its the HU, it wouldnt matter where you get your input from. I would assume that TT wouldve looked into that and would have provided a harness to tap into the best source (pre or post amp).

 

Yes, based on this video: 2022+ Toyota Tundra How to obtain subwoofer signal from your stock JBL Audio System. Add a subwoofer - YouTube.
.
It just doesn't provide clear instructions on connecting the harness to the LOC. I've reached out for detailed instructions or a video demonstration

 

I spoke with a representative from Taco Tunes who mentioned that their wiring harness is color-coded, which simplifies the installation process. Although they didn't specify whether they tapped into the front or rear outputs, they assured me that the LC2i Pro would resolve any issues, though I remain somewhat skeptical. Nevertheless, I consider it the most straightforward solution for achieving the correct output for an aftermarket amplifier and subwoofer.

 

I just purchased the AHH harnesses and asked them to pull out the front (door) and front tweeter signal wires. Send those to the LC7i and have it SUM those two. Should get me a full range signal. Fingers crossed.

 

Please report back with some pictures on how the installation goes.

 

I just heard back from Taylor from Tech12volt and they currently don't have any configurations for 2024 yet. He said they're working on it. They are also ok after the storms.

 

Will do, but it will be ongoing, not all at once. Currently building the sub box.
Or more accurately, repurposing and rebuilding an existing box I've had in a previous vehicle. And using the same sub.
Most of my (audio) junk is old and well used, but proven, to me anyway. Hmmm...I'm pretty sure there's a metaphor in there.

Current parts list:

• Integration: Auto Harness House Harnesses: AHH-7881 30 pin and AHH-7583 24 pin
• LOC: Audio Control LC7i
• EQ: Clarion EQS746
• Amp: Precision Power P900.5
• Sub box: DIY, 3/4" MDF, sealed, single down-firing 10", approx. .65 cu ft.
• Sub: MB Quart DS-251 Discus, dual voice coil, 4 ohms ea, will run at 2 ohm

That's phase 1.

Phase 2 is front and rear components. Don't have those and haven't settled on them yet.

Unless someone talks me out of it, I'm seriously considering ditching the 3 dash speakers altogether. Unless I just leave them powered by the JBL and see how it sounds first. I can always disconnect them later.
I don't care for the stock staging at all. Way too dash-forward focused. If I can get them to be more fill and less prominent, I'll keep them in the mix.

 

I see you're going with the LC7i, where you can control more of the full sound, not just the Aftermarket Amp/Sub output. I'm sure this will deliver the best sound overall. No question.

 

I believe for 3rd gen’s the Taco Tunes and AutoHarnessHouse harness is an 8 wire bundle that plugs in behind the head unit rather than at the factory amp. Based on that my guess is that either a) it’s more convenient to get signal there, which would make sense since you can tap front left, front right, rear left and rear right according to the AutoHarnessHouse pics, or b) because the signal pre-jbl-amp is more clean, or a combination of a and b.

Since the AutoHarnessHouse harness lists the 4 FL, FR, RL, and RR as options to self tap, my guess is that the factory head unit outputs those as full signal, and then the signal is “copied” at the JBL amp, which then sends the signal onto the dash corners and tweeters. In my non-jbl 2021 the corners and tweeters have capacitors wired in line acting as physical base blockers, i’d guess a similar design is used in a JBL truck, but as far as sub signal goes, I’m guessing the amplifier has a built in low pass filter.

 

@Snert:
I believe this is the harness you are referring to:
https://www.autoharnesshouse.com/82193_info.html

This is the AHH-2477 that attaches to the head unit in the dash.
While AHH's website does not specifically say so, this harness is only used for the non-JBL head units to pull speaker signal. The reason for this is you will lose balance/fade functionality at the head unit if pulling from here on a JBL system.

As I understand it, the head unit and JBL under-seat amp are joined at the hip and one needs the other in order to fully function.
I find the AHH website to be incredibly frustrating with missing pages (or intentionally left out?) and broken links.
On this page: https://www.autoharnesshouse.com/41112.html
you will find the following statement:
**If you need an adapter for a JBL vehicle, please email us and we can provide an adapter that has the correct wiring for your vehicle**

In March of this year I had an email conversation with an AHH rep (Technical Support and Sales Engineer) who provided me with the correct p/n's I would need for a JBL equipped 3rd gen.
The following link shows the two harnesses that I purchased:
https://www.autoharnesshouse.com/JBL-HarmanKardon-Jumper.html

This page is not currently "findable" from their website that I can see.
(Maybe from the Subaru/Harman Kardon pages but not Toyota/JBL?)

 

We'll that saved me a lot of time. Appreciate the insight on this

 

When you get the wiring harness - can you share the instructions on how you're splicing the wires? Where are you going to put your LC7i?