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Stock amp with an aftermarket head unit?

Ultra440

New member
Anyone have any experience with this? I just got a new HU and would like to know a little more before I dig into the install. Theres 3 different pre-outs on the HU- woofer, front and back. However, I'm not sure how the stock amp runs to the stock HU.

I have an amp powering 2 12s, the stock amp and the 9 speaker system that came in the car. I assume the stock amp powers the 2 6x9s, and the others are powered by the HU.

Power wire already running from battery to amp, remote wire is tied into an add a fuse. For an input on my subs I was using some little contraption that ties into your 6x9 speaker wire and pulls signal from that and sends to your amp.

I bought the harness, I'm hoping all I have to do is plug it in and run the RCA jacks for everything to work as it should.
 


What is your question? If you have a stock amp, it is powering all of your factory speakers. The "contraption" you tapped into for the signal to your aftermarket amp is called a LOC (Line out Converter). The Sub pre-outs are obviously for the sub (This way you can control the sub level from your HU) The other outs are for if you amplify the rest of your speakers. (Which if you're leaving them stock, I wouldn't. Or you'll be replacing them soon). If I missed anything, please ask a more focused question.
 
Where does the factory amp get it's signal? I've already replaced all of the rear speakers (pioneer 6x9s and infinity 3.25s in the bak doors). Will probably do the front doors 5.25s and tweets soon.

I'm just not sure how to go about this, I don't plan on buying another amp.
 
More specifically I guess I want to know how easy it is to keep the factory amp powering the speakers. I'm assuming the stock amp uses some kind of line out converter itself for a signal, as there are no RCA jacks on the amp (I don't think).

Keith, I appreciate your help on my audio threads!
 
I believe the stock amp is powered by one of the harnesses on the back of the stock hu. But ive heard that if you get a aftermarket hu that you can bypass the stock amp because an aftermarket hu will send more power than the stock amp will. ( not sure jow true that is though.)
 
I believe the stock amp is powered by one of the harnesses on the back of the stock hu. But ive heard that if you get a aftermarket hu that you can bypass the stock amp because an aftermarket hu will send more power than the stock amp will. ( not sure jow true that is though.)

This is what I was debating. I think most of my aftermarket speakers are 100w max, and may or may not run around 25w rms per speaker. My head unit is good for 50x4, I think 23 rms... BUT I have 9 speakers. Split that wattage all out of the head unit and it's LOW. I know I'm leaving this a little open ended but...

Thoughts?
 


No, I would just use the factory amp to power your speakers. Even though the HU says "50wx4", you'll only really see around 11-24w. Just an FYI, the rear outputs of the factory amp are separated. Low/mid range goes to the 6x9's and high range goes to the 4" speaker. So if you put in a 2way or 3way 6x9, you're only using the woofer of the 6x9.
 
No, I would just use the factory amp to power your speakers. Even though the HU says "50wx4", you'll only really see around 11-24w. Just an FYI, the rear outputs of the factory amp are separated. Low/mid range goes to the 6x9's and high range goes to the 4" speaker. So if you put in a 2way or 3way 6x9, you're only using the woofer of the 6x9.

I see. Yeah I got 2 ways but they were cheap enough and sound good. So am I looking at plug and play with my harness or do I have to run RCA jacks to the factory amp? (I've read since there's no rcas on the factory amp that you can cut the RCA jacks off on one side and splice them into the wires going into the factory amp input, leaving all the speaker output wires where they are).

Ill be digging into this install as soon as I get my swi, taking a while (eBay)... I'll know more once I get the ok HU out
 
I got one off eBay, didnt know there was more than one type! It's looks like any other harness I've used, 8 speaker wires, 2 powers, remote illumination etc
I also got a PAC-swi for my steering wheel controls
 
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Below is the harness crutch field supplies. The harness I have may or may not have the factory amp/ground wires but given this info below and what youve told me I should be able to make do with what I have and get er done. Thanks

12V constant power
12V switched power
chassis ground
factory amp shield ground (connect to receiver chassis if engine noise is heard)
power antenna turn-on
factory amplifier turn-on
dimmer
left front speaker +/-
right front speaker +/-
left rear speaker +/-
right rear speaker +/-
See more info on this item
 
I feel like I left the facotory amp wire unplugged. The speakers all seemed to work and squeezing the head unit into where the factory unit was took all my energy.i was frustrated and threw it all back together. May try to locate te remote wire going into the amp and just hook that up to my existing remote wire for my aftermarket amp. Or leave it. Sounds good.

Thanks again for your help man.

Any idea what color the factory amp remote wire is?
 
If the speakers are running, the factory amp is turned on. So no need to connect the remote line to the factory amp. I read that the Park Avenues have a hard time fitting aftermarket HU's. It says they are cutting out the plastic behind the radio to make it fit with the harness.
 
If the speakers are running, the factory amp is turned on. So no need to connect the remote line to the factory amp. I read that the Park Avenues have a hard time fitting aftermarket HU's. It says they are cutting out the plastic behind the radio to make it fit with the harness.

Awesome. I was hoping that was the case. And yes, holy tight fit batman. I dremmeled out as much plastic as I could but the problem plastic that the HU is hitting, I'm pretty sure, is my drivers side vent duct... So yeah, I left that alone. I hacked up the mounting kit a bit because the HU wouldnt go all the way in, the bracket was sticking out maybe a 1/4 in. on the right side only. Took too big a chunk off so I have a hole in the plastic housing but I'm gonna live with it. All in all, the Bluetooth and cool lookin HU was worth the $150 I paid for the complete upgrade, not to mention all of the extra features it has..
 


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