Use existing speaker wire 2018 NON JBL with Factory Amp for New Amp and Speakers?

What's up guys? I'm in the minority here since I've already upgraded my head unit and 95% of the installs here are using the stock headunit. I'm looking to install new speakers and an amp. Components up front, Coax in rear, and a JL 400/4.

I'm trying to make sure I understand everything before I jump into this, tear my truck apart and realize I need additional parts.

Since I have an aftermarket head unit, I have no need for a LOC. I am going to run RCAs from the head unit to the inputs on the amp. I'll run a new power wire from the battery 0ga to a fuse block then 4ga to this amp so I can set it up to add an amp for a sub later.

It seems to me there is some sort of adapter to reuse the existing wires to the stock speakers that I can use to hook up to the output of my new amp. I will re-wire the truck if I absolutely have to but only pushing 75w RMS to each speaker with my new amp I figured I'd be okay using the factory wiring.

I'm confused because most people are using the high voltage inputs because they don't run new RCAs from the stock head unit. In my mind this should be simple but I know there is some funky wiring going on in this truck when it comes to the audio "system".

I've also seen posts where people run the output of the amp back to the headunit? That completely baffles me. Seems like I should just be able to tie into the stock speaker wires going to all of the doors at the factory amp location.

Am I missing something?

 

Also, I've been trying to work with James Tech12v but he keeps saying that upgrading the speakers and putting a new amp in will sound worse than the stock system. Even after multiple explanations, I can't understand what he's trying to relay. He stated that there will be no bass at all in the system. I have a hard time understanding how this could be the case.

 

I would imagine that James is saying this because nowhere in your plans do you mention a subwoofer -- which I think is an essential part of any stereo upgrade in our vehicle. You might want to consider a JL 5 channel amp and a subwoofer instead of/in addition to what you are planning.

Dave

 

100% getting his ported box and two 10s to finish my build along with another amp. I’m starting with the speakers because I already have the 400/4 and would like to get it sounding decent.

 

People run the speaker wires from the amp back to the head unit because it is a convenient location to connect with the stock speaker wiring harness. Some people cut the factory speaker wire harness and connect the appropriate speaker wires from the amp. A cleaner install is to use a speaker wire T-harness so the stock harness isn't cut. The T-harness allows the speaker wires from the amp to be connected to it and then plugged into the stock wire harness locations. Some people use a 9 conductor wire set (8 speaker wires and 1 remote turn on wire) to make this even easier. Stinger makes a product called Speed Wire and there are other cheaper alternatives. I think I have explained this correctly.

https://stingerelectronics.com/products/9-conductor-speedwire-20ft

 

I prefer running my own speaker wires, but that s just me. I would rather have a new audio system in a self contained circuit rather than running through the truck wiring. It simplifies troubleshooting, and if one chooses to lay down deadener, then the carpet is already up. It s easy to run the wires/rca s then. I did my system like you are talking about. After a new headunit I got new speakers, a 4 ch amp, and got them running good. I still plan on a sub, but waiting for summer to do that. With good mids in the back doors, and 2 way components up front, it sounds great. A sub would sound better obviously, but its far from essential.

 

I had my wire gutted but i didn't do it myself.

Took them two days for the install but they did a great job and the sound is like a concert

 

Any tips for getting it through the front and rear doors cleanly?

 

Very carefully. Just like @jwatt, I too will only run NEW wire to all of my speakers. The OEM wiring is a ridiculously small gauge. For the shit, OEM JBL speakers, it's probably fine. But for quality, amp-pushed components, new, larger gauge, 100% oxygen free copper wire is the way to go (and yes, you can get it on Amazon). If you try to push a lot of power to the door speakers, through the tiny gauge OEM wiring, you could cause the amp to get hot, or go into "protect mode". And copper clad aluminum wire, also called "CCA" (ie. el cheapo wire) degrades much quicker over time, is incapable of carrying as strong a signal vs. 100% O2 free wire of the same gauge. I mean, this is a $40-50k vehicle. Why cut corners? Do it the right way the first time and you will be so much happier!

If memory servers, for each door, I used a small diameter drill bit and carefully drilled a hole through the OEM white plastic plate/plug thingy (being careful not to hit any of the OEM wires) that all the door wires pass through. Then, I pushed the new (100% OXYGEN FREE!!!) wire through the new hole. Next, I took a long, flat head screw driver, and taped my new wire (100% OXYGEN FREE!!!) to the flat head, and carefully guided it through the rubber wire/door tube, and into the door. Of course, you will have to pull the door panel off and the big plastic/cellophane cover off of the internals and pull the wire through. But, it really is not that hard.

I know I keep harping on the 100% O2 free wire, but on one of my earlier installs on an old Xterra (I don't know what the hell I was thinking buying that POS), I used CCA to save some money. Good grief! My 4 channel amp kept getting hot and going into protect mode. Even my CCA hot wire and grounds began corroding prematurely. Just utter crap. Make sure that you also use 100% O2 free wire for your hots and grounds!!!!!!

 

I've got some pictures in my build log (in my signature) towards the end.
Its a bit of a pain to run it through the rubber boot but not the end of the world. i ran it with the factory wires for a while, just depends on if you want to do it correctly or just get it done. Also the rear doors use a plug that you will need to drill a hole through, i didn't want to do that, so i kept the rears using the factory wires.
12ga ofc!

 

If you take off the trim and look at the wiring entering the rubber boot it s not hard to imagine a way to fish a new wire through. I taped wire to a coat hanger and it was simple actually. Additionally, one needs to consider the location of power wires/cables if they run to back of cab, and where and how the door speaker wires cross them. Safest bet is to be sure they cross at a right angle, (90 degree), to power lines. Running them paralell doesn t always cause problems, but it can cause noise in some systems. With that in mind, I also like to mount amp/s on 1" stand offs. That way there are more wire/cable routing options; the goal being minimal influence to speaker or rca signals by EMI of power lines. (This site explains it much better).

 

If you want to use your new amp to drive the door speakers with factory wiring you can do so. Full spectrum channels from the OEM head unit go to the OEM amp on the 12-pin J145 (pins 1/6 L and 2/7 R) and are output from the amp to the doors on the 10-pin connector J144. Pins 1/5 are the right door and pins 2/6 are the left door outputs from the factory amp.

Since you didn't indicate how your aftermarket HU was installed or configured, I don't know how your audio is routed at the moment. If you used plug and play adapters and didn't splice or re-route anything, you should be good to go with the signal path info above.

 

I agree. It is baffling why someone would do that. The only components I can imagine sending amp output to is a crossover, or speaker/sub. I don t even think a dsp could handle amplified signal. Where did you see these posts?

 

DSPs are preamp devices.

No one runs it back to the amp, that would be a closed circuit that never reaches a speaker, and yes of course the HU could not handle any real current. I would love to see this post too as it surely would involve troubleshooting the short that they essentially would have created.

Unless they're referring to reusing the stock wiring and a breakout harness or T harness. In that case there wouldn't really be any concern unless you were considering running at least 100W per channel. Even then not much concern.

Professional shops use stock wiring all day long. Primary reasons for replacing it is the use of passive or active crossovers (even though stock could still be used, but it results in essentially the same amount of work) and that the customers spending hundreds on a single speaker set will likely want to "get the most out of the speaker". Voltage delta from going from the stock 20ga to say 16ga is going to be so small it wont even be audible to the human ear. I suppose at very high current or very long wiring there would be a concern for over temp occurring on the amp, but that situation would require some hefty power or super long distances. Nothing 99% of the people on here would see either of.

Anyone here installing <100W per channel amp will be safe on stock wiring.

 

I've ordered 100' of OFC wire. I too was once young, dumb, and on what was beyond a tight budget. Luckily I'm a bit older, have a little more sense, and have the means to get the correct parts to do a clean and efficient install. I'm only running 75w to each speaker so I kind of want to see what it sounds like on the stock speaker wire. With a 3yo running around the house like a madman, the wife would kill me if I spent all weekend doing this project and would give me a much harder time when it was time to throw a sub in. But if I think it's better suited to run new wire, I have the supplies and I'll just make it happen. It doesn't seem too hard.

 

Running a PDX V9 with 100 watts RMS per channel;
I ran speaker wire for the front door components but used the stock wiring for the back doors of my DC.
The rear doors are minimal fill and threading new wire thru that boot was gonna be a mother fu(ker..
You have to take that center panel (between the front and rear doors) off a DC to feed it thru.
I should have done it when I stripped the interior for the sound deadening, but didn't think about it.
It all sounds just fine the way I did it.

Go ahead and run your sub speaker wire while you're doing this.

Side note;
I disconnected all 3 dash speakers since they screwed up the sound of my front door components..

Good luck @SloppyJ .

 

I've ordered the 4438 harness from autoharnesshouse to use in order to hook up the new amp under the seats and at least give the stock speaker wire a shot which would save me quite a bit of time I imagine. Seems pretty cut and dry on how to hook up the stock system to the outputs on the amp and the 12v acc wire.

The Kenwood is hooked up with a maestro and the instructions directed me to wire all of the outputs from the head unit (FR, FL, RR, RL) to the harness. So as it sits now, all channels on the head unit are providing power and everything is functioning correctly. The signal path to the new amp will be via RCAs so that's easy. I'm still very foggy on what speakers are powered from the head unit and which speakers are from the amp. I've seen a few different schematics.

I was told that I don't need to unhook any of those outputs that provide power to the stock harness from the headunit. I can't really figure out if those are used for the input signal to the stock amp or if they are actually powering speakers. Still trying to make it make sense in my head. It seems like the head unit is powering my dash speakers and then the amp routes power through the corner dash speakers back to the front doors. I imagine the head unit is also powering the rear tweeters. Without understanding exactly what is powered by the head unit and what is powered by the amp and how they will interact when I install a new amp, I was planning on just leaving the head unit wired as is and hooking up the amp with the new harness and start testing and go from there.

Maybe I'm missing a key component to make this make sense to me? The stock wiring and how it's configured has really thrown me for a loop with there being power from the head unit and power from the amp and then power being fed through speakers to get to other speakers. Whoever designed this was a real winner.

Page 215 of the PDF in the link below are the maestro instructions.

https://images.idatalink.com/corporate/Content/Manuals/RR-TOY/ADS-RR(SR)-TOY02-DS-IG-EN_20210201.pdf

 

Appreciate the advice my man! I'll have to pull the back side of the carpet back out when i do the sub to sound deaden the rear wall and the rear floor section when I put the subs in so I was planning on doing all of the sub stuff at that point. But I already have the wire and I might as well just run it while I have it all torn apart anyway.

 

On your non-JBL, all 3 dash speakers run straight off the HU.



If you connected your new HU to the stock speaker wiring outputs (front and rear), you'll have sound from your dash speakers.
It goes from the the HU, to the side dash speakers, to the dual coil center speaker.
If you buy and install a decent set of components in your front doors, I'd suggest disconnecting the dash.
Reason is, your doors will be powered by the amp (75 watts), the dash powered by the HU (maybe 15 to 20 watts).
Also if your HU has TA (time alignment) having the dash speakers running off the HU could cause issues with that.

 

I can just unplug the actual speakers correct? No need to actually disconnect the FR,FL channels from the back of the head unit. I do have the time alignment with my head unit and was looking forward to actually seeing how it worked with the new speakers. I like the idea of front fill in those dash corners but I've already decided that if I want that in the future I will buy another matching JL 400/4 amp, add legit 3" speakers up there and run everything active. Always gotta have those future goals!

EDIT - Thanks for the diagrams. Makes sense now and that's what I needed. I'll just unplug those suckers. Seriously whoever thought that was a good idea needs to get kicked in the sack.

 

By all means try the dash speakers and see how it sounds.
It might work for you..

Yes you can disconnect (unplug) the side dash speakers and that will in effect disconnect the center.

I even tried James' Kenwood side with his twin JL Audio tweeter center, and it just didn't sound good with my amped Focal PS165FX fronts.
Not that there was anything wrong with what I bought, it just didn't sound good with what I had, so I sold them on the forum instead of returning them.

James is top notch and has been very helpful to me thru emails..
If I was starting from scratch, I wouldn't hesitate to buy one of his packaged systems...

 

Nah, not hard... just tedious.

 

I reached out to him when I got my head unit and he was extremely helpful and compiled all of the parts I needed to hook it up. He sent me the part numbers telling me I could get it cheaper if I didn't order through him. I told him I don't work like that and asked him to send me a paypal invoice and I'll get him paid for the parts. Super stand up guy.

I coordinated with him on my future build and that's when things started to get weird. I had planned a speaker upgrade first (that I'm doing now) and the second phase was adding 2-10s, a box from him, and another amp. When I was ready to buy my speakers I shot him an email and I got some weird responses back. Short, not well written out and hard to follow. He told me upgrading speakers isn't a good idea and I would lose all of my bass response. I was confused and kept asking questions but the only answer I got was that "Since the new speakers have crossovers it will filter all of the bass out." I still don't understand what he was trying to say. I asked him what his recommendation was and it was to run "efficient coax speakers off the head unit." I reiterated that I will be adding a new amp but still didn't get much help. I decided that I was just going to piece the system together on my own at that point so I scraped together some ID components and some ID coax, an amp, wiring, and some adapters and install parts and decided to just make it happen. In my mind there's no way that components in the front, nice coax in the rear and a nice amp to run them can sound worse than the stock setup.

If I don't construct my own box, I've designed an externally ported box that puts the port out under the back seat, I will go with a box and subs from him. From what I've seen, his boxes look the best out of all of the premade options and he actually adjusts it to the subs you get which is awesome. He quoted me some good prices for that equipment. I know he's going through a office remodel and I'm sure he's super busy so I gave him the benefit of the doubt on the speaker upgrade in case I didn't explain myself well enough.

 

James is great.
But if you want 1 more option on your sub box, look into these guys.
Toyota Tundra Archives - NET Audio
They will build the box to the specs of whatever sub you plan to use..

I almost bought a 12" box from them.

I've got a JL Audio twin 10" Stealthbox I haven't been happy with for 5 years.
After A LOT of research, I rewired it from series at 6.5 ohms (how it came when new) to parallel at 1.9 ohms.
After turning the sub amp gain down, it finally sounds great.

 

Sounds like you didn't have enough power going to it before. I was reading that those slim JLs like more power. Like 500w each. Thanks for the heads up on the other box. I'll check it out.