Upgrading JBL Amp w/ Aftermarket Head Unit

Im currently trying to decide how to upgrade the stock JBL amp in the 1794 Tundra.

I have already replaced the stock speakers with Alpine S Series component speakers in all the doors with crossovers.

I also had already put an aftermarket head unit in (Sony 9500ES) with the harnesses to retain the factory amp and steering wheel controls.

The sound from the amp still has me feeling lack lustered in terms of the volume. So I figured my next step would be to replace the factory amp. I’ve been trying to research a way to replace the JBL factory amp with a plug and play bundle/harness. But everywhere I look, it says “non-jbl amplified”. Because most people trying to do so want to keep the stock head unit I guess? I would prefer to not have to cut or splice any wires. Just unplug old amp, plug in new amp and call it a day.

Idk if Im just overcomplicating it since I don't have the stock head unit or not. But since I have it wired as if the stock amp is still there, Im unsure if I would have to undo that when hooking an aftermarket amp up.

Any help or insight would be greatly appreciated. Thanks!

 

@1lowlife any idea who the JBL expert is that might be able to get the OP started in the right direction? I don't know if this falls into the LOC category or not.

 

I know very little about the JBL system, other than that the factory amp powers more stuff than the non-JBL.

On the the non-JBL dash speakers run off the HU, the doors run off the amp.
I think the rear door tweeters might run of the amp in Crewmax, I have a double cab..

All the speakers in the JBL run off the OEM amp.

Welcome to the forum @TundraDave14
Honestly, your best bet would be to ditch/bypass the factory amp.
I know it's a little harder to do than the non-JBL, even more so that it powers the crappy JBL sub.
I'd also recommend a Maestro interface to retain your steering wheel controls with the new HU.

The OEM only sends mids and lows to the OEM front 6X9 speakers.
It sends a separate signal to the side dash and front door tweeters.
Then it also sends a separate signal to the center channel.

You can look thru the wiring diagrams to understand your JBL system better than I could explain.

Ultimate TUNDRA Wiring Diagrams Collection | Toyota Tundra Forum (tundras.com)

 

If you gutted the system except the JBL amp you don't need to keep it. Replacing the JBL Amp is an issue if you are keeping the stock head unit. The two components work together, if you replaced one you can replace the other.

 

Hi. I'm in the same boat. My 2014 1794 Ed had pitiful sound so I swapped out the factory JBL head, amp and speakers for Sony & Kicker. The midrange and high end are better to my ears, but the bass is sadly deficient. I guess I'm going to be adding a powered subwoofer. I won't be making a trip to Taco Tunes in San Antonio so suggestions welcomed.

 

You've got a couple of options for replacing the JBL amp since you've already replaced the head unit. As others have stated, in non JBL trucks the head unit powers the center speaker and the dash corners. In JBL everything runs through the factory amp. I've attached a PDF of the JBL wiring diagrams for 2014. It looks like the tweeters are wire in parallel with the door woofers.

Are you wanting to keep the center and dash corners? I have a non-JBL truck and removed mine when replacing my door speakers and adding tweeters and haven't missed them.

From what I'm thinking, you've more or less got 2 options of how to wire things up:

Option 1: Get a 5 channel amp, or a 4 channel and a mono. Run power and ground for aftermarket amp. Run RCA's from your XAV-9500ES to the aftermarket amp. Get a harness that plugs into the factory speaker output plug at the factory amp location. Solder/splice the aftermarket harness onto your aftermarket speaker outputs to connect channels Front Right (FR) Front Left (FL) Rear Right (RR) Rear Left (RL) and Sub Output on 5 channel. If using a 4 channel and mono to power your JBL sub, you'd just need some RCA Y splitters along with a fused power distribution block and non-fused ground distribution block to wire up both amps. To illustrate (again this ditches the center, and dash corner speakers). This would not be cutting any factory wiring. The only splicing or soldering of connections you would need to make would be between the aftermarket wire harness/plug and the speaker wire outputs coming from your new amp.







Option 2: Same as above. Only difference would be that you would get 2 factory amp integration harnesses. In this case, you would have one harness that plugs into the wires/harness coming from the head unit. You would then need either a line output converter, or an amp that accepts high level inputs.

If using a LOC, the connection chain would Go Head Unit>Factory Plug At Factory Amp Location>Aftermarket Plug>LOC>Amplifier RCA Inputs
To Illustrate (not including power/ground/remote to amp and power/ground/remote to LOC depending on what type you use):





If using high level inputs, the connection chain would go Head Unit>Factory Plug at Factory Amp Location>Aftermarket Plug>Amplifier High Level Inputs
To Illustrate (not including power/ground/remote to amp and power/ground/remote to LOC depending on what type you use)::




All things totaled, you're most of the way to better sound. Check out AutoHarnessHouse.com. Toyota Entune Amp Upgrade for Tundra and Tacoma (autoharnesshouse.com) They have a slew of different harnesses and for JBL vehicles they just have you email them to make the correct harness(es) you'd need.

 

Sorry forgot to attach the PDF

 

@Snert

would this work if I still want to keep using my corner dash and center? Your diagrams really helped me understand the wiring.

 

Do you have JBL or no JBL? In a JBL truck, everything is powered off the JBL amp. In a non JBL, the dash corners and center are wired together and powered off the head unit. If replacing a JBL, you’d need an amp with more channels, remove the factory dash corners and center speaker, or replace them with 4 ohm and then you could do some wiring trickery to basically do an amp bypass and power them off an aftermarket head unit.

 

Thanks snert. I have the jbl version. Going ti get rid of the head unit also. But want to keep all speakers. Although if it proves too difficult then might just get rid of them.

 

This is what the speaker wiring looks like in your truck @cowbear



As you can see, everything comes off the JBL amp under the passenger seat. The center speaker and the two dash corners are wired independently. I'm not sure what ohm rating the speakers in the JBL trucks are in the center and dash corners. An aftermarket head unit and really any head unit for that matter will only be able to run 4 ohm speakers. Are you looking to replace any speakers, or just the head unit? What about replacing the amp? I guess what all are you wanting to replace?

 

I want to replace head unit. My dash and center were replaced with some recommendations I found here. I dont recall the name right now. I have a 4ch amp laying around so was hoping to use that and still keep my center and dash. Looks like I either need an 8ch amp or wire the 3 to my head unit.

 

That's correct. If you wanted to use that 4 channel, you certainly could. Depending on which speakers you have in the dash corners and center, and which head unit you get, they might be underpowered but would still probably sound just fine. What kind of 4 channel amp do you have? That will determine how you could potentially wire things, but you'd basically have 2 options.

1) Install new head unit and run RCA cables to your 4 channel amp for input, use a factory integration wire harness for output.
2) Install new head unit and use factory integration harness for input and output at new amp (if amp accepts high level inputs).

In either case, you'll at least want a factory integration harness for the output side of your amp so that you can re-use the factory wiring for your new speakers. Depending on how powerful your 4 channel amp is, it may be too powerful for the factory JBL speakers as they're not meant to handle a ton of power. If that's the case, I'd recommend getting new speakers for the doors as well, that way you don't risk blowing your speakers.

AutoHarnessHouse.com sells factory integration harnesses. This is the link to their Non-JBL harness with instructions to email them if you have a JBL truck so they an create the correct harness for you: Toyota Entune Amp Upgrade for Tundra and Tacoma (autoharnesshouse.com) They would probably be willing/able to loop the signal for the center and dash corners for you. It seems kind of silly but since everything in a JBL is powered off the amp, that means the signal goes from the head unit, down to the amp under the passenger seat, and then back up to the dash corner and center (and all other speaker locations). If you looped the signal for the dash corners and center at the amp location, you could effectively bypass the amp so that the signal is going straight from your new head unit to your dash corners and center.

For your doors, if you replace with a component set, depending on the set, you'd have to figure out where to put the passive crossovers. Easiest place would be in the doors themselves. You'd use the factory wiring for the door woofer for input into your passive crossover, and then run short lengths of wire within the door itself to your new door woofer and tweeter. I always prefer to put the crossovers somewhere accessible so you can tweak them if need be. If you go that route, it would make the most sense to put the crossovers next to your new amp under the passenger seat, and then you'd go from amp output to crossover input, and then again reuse the factory wiring for output to the door woofer, but then the downside is you'd have to run new wiring to the tweeter or figure out integrating into the factory wiring running to the factory tweeter location. Some component sets will have inline crossovers so you don't have to worry about all that. Other option is coaxials and also wouldn't have to worry about any of that.