Amp Bypass
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From: Sasebo Japan
Amp Bypass
I didnt come up with this but Emperor gets a million questions aday so i figured i would post this...this is for people wanting to run aftermarket amplifiers
Originally Posted by EmperorJJ1
To do a successfull amp bypass it requires a few steps but non are particularly hard you must just go slow and double check yourself.
Equiptment needed (read the instructions before purchasing to minimialize excess... also most of this can be found at a local audio shop. Try there first because they will often sell staight up install stuff for cheaper then online BUT buy it from where u get the best price ) = 9 wire speed cablehttp://www.scosche.com/products/productID/980
remote wire http://www.scosche.com/products/productID/960
Rcas
wire cutters/crimpers
crimp caps www.installer.com/photos/cc1614s.jpg
First i would hook up the amp power and ground. Personally i would screw it to the back of the seats but you can mount it wherever (preferably not on a subwoofer box).
After you get it mounted i would go ahead and run the rcas from the HU to the amp. The techniclly better side to run them on is the passenger side so you dont interfire with the stock batt power wire but you can run them on the drivers side to minimize the panels you have to take out (although the chance of noise increases when you run them by the power wire especially with a mids amp) You need to run either 1 set of 4 chan rcas or 2 sets of 2 chan rcas. If you run 2 seperate sets make sure they are labled somehow before you put them in the car (electrical tape is a good way to not only lable a set but also keep the wires together for easier installation)
You must now run the speed cable from the aftermarket amp to the facotry amp. You can go ahead and hook up all the connections at the aftermarket amp if you want or leave them for later whatever you prefer... on the speed cable there are 9 wires 8 speaker wires and a remote. they are 100% identical other then color but make it easier on yourself or any other installer that works on your car and hook it up using the "standard" colors when hooking it up
Blue= remote
white= left front
grey= right front
green= left rear
purple= right rear
Also its easier to work with the speed cable if you cut off a fewn inches of the outer insualtion on each end of it. this will allow you to work with each individual wire
This is where it gets confusing so read carefully...
you are now going to remove a single connector from the factory amp. This is going to be the only connector you are going to need to splice and connect to the speed cable... When you do so you must terminate any stock connection and re route it to the speed cable... you cannot use t taps for this unless you plan on blowing any speaker hooked up. If you have the stock sub running off the stock setup you cant cut those wires from this connector and u must leave all the amp connections intact other then the ones you are cutting and crimping onto the speed cable. If you dont have the stock sub working then i recommend completely removing the amp to prevent any type of power randomly going odd places.... you can also at your disgression completely remove this harness.
below is the wire colors to the harness you will be splicing. Its the first one on the list
https://www.cobaltss.net/forums/electronics-audio-video-49/cobalt-audio-pinouts-2823/
the last thing you need to do to make this work is extend the blue remote wire to the aftermarket HU.
Now see that wasnt so hard was it? Well worth the effort for better sound
Equiptment needed (read the instructions before purchasing to minimialize excess... also most of this can be found at a local audio shop. Try there first because they will often sell staight up install stuff for cheaper then online BUT buy it from where u get the best price ) = 9 wire speed cablehttp://www.scosche.com/products/productID/980
remote wire http://www.scosche.com/products/productID/960
Rcas
wire cutters/crimpers
crimp caps www.installer.com/photos/cc1614s.jpg
First i would hook up the amp power and ground. Personally i would screw it to the back of the seats but you can mount it wherever (preferably not on a subwoofer box).
After you get it mounted i would go ahead and run the rcas from the HU to the amp. The techniclly better side to run them on is the passenger side so you dont interfire with the stock batt power wire but you can run them on the drivers side to minimize the panels you have to take out (although the chance of noise increases when you run them by the power wire especially with a mids amp) You need to run either 1 set of 4 chan rcas or 2 sets of 2 chan rcas. If you run 2 seperate sets make sure they are labled somehow before you put them in the car (electrical tape is a good way to not only lable a set but also keep the wires together for easier installation)
You must now run the speed cable from the aftermarket amp to the facotry amp. You can go ahead and hook up all the connections at the aftermarket amp if you want or leave them for later whatever you prefer... on the speed cable there are 9 wires 8 speaker wires and a remote. they are 100% identical other then color but make it easier on yourself or any other installer that works on your car and hook it up using the "standard" colors when hooking it up
Blue= remote
white= left front
grey= right front
green= left rear
purple= right rear
Also its easier to work with the speed cable if you cut off a fewn inches of the outer insualtion on each end of it. this will allow you to work with each individual wire
This is where it gets confusing so read carefully...
you are now going to remove a single connector from the factory amp. This is going to be the only connector you are going to need to splice and connect to the speed cable... When you do so you must terminate any stock connection and re route it to the speed cable... you cannot use t taps for this unless you plan on blowing any speaker hooked up. If you have the stock sub running off the stock setup you cant cut those wires from this connector and u must leave all the amp connections intact other then the ones you are cutting and crimping onto the speed cable. If you dont have the stock sub working then i recommend completely removing the amp to prevent any type of power randomly going odd places.... you can also at your disgression completely remove this harness.
below is the wire colors to the harness you will be splicing. Its the first one on the list
https://www.cobaltss.net/forums/electronics-audio-video-49/cobalt-audio-pinouts-2823/
the last thing you need to do to make this work is extend the blue remote wire to the aftermarket HU.
Now see that wasnt so hard was it? Well worth the effort for better sound
Last edited by TommyP; Jul 15, 2011 at 09:35 PM. Reason: Removed part of quote as requested by Emp
right if you are installing an aftermarket amp for your mids then you will need to do an amp bypass... Only difference between doing an aftermarket HU and the stock HU is the amp bypass is significantly harder using the stock HU. It can be done (i was actually going to do one in my GF's car but got her a new HU to make it easier)
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Joined: 05-10-05
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From: Dekalb, IL
I had tried sucking signal after the Stock amp for a RF 360.1, and it wasn't worth it. I ended up removing the factory amp and getting my signal directly from the back of the Stock Radio. (the wire codes in the other sticky were spot on and much appreciated)
As I read through this sticky, What it looks like your doing it either Running a new amp and headunit with the stock Speakers, or trying to limit running new wire to the doors but using the stock wireing. (I wouldn't do either personally, but this will definately work, and if your not looking for high end, it will probably work well. (Speed cable rocks)
Anyone know exactly where the Power wire runs from Battery to Engine? I thought mine ran down the middle of the car, but maybe I wasn't looking very hard.
As I read through this sticky, What it looks like your doing it either Running a new amp and headunit with the stock Speakers, or trying to limit running new wire to the doors but using the stock wireing. (I wouldn't do either personally, but this will definately work, and if your not looking for high end, it will probably work well. (Speed cable rocks)
Anyone know exactly where the Power wire runs from Battery to Engine? I thought mine ran down the middle of the car, but maybe I wasn't looking very hard.
it enters a giant grommet thru the firewall on the driver side runs under the carpet on that side until the middle of the seat and goes to the middle and runs thru until the back... all under the carpet until the rear seats
pretty much just not running new wire to each speaker. Not really necessary in most installs. but i def would like to know how the hell that molex plug gets off
I had tried sucking signal after the Stock amp for a RF 360.1, and it wasn't worth it. I ended up removing the factory amp and getting my signal directly from the back of the Stock Radio. (the wire codes in the other sticky were spot on and much appreciated)
As I read through this sticky, What it looks like your doing it either Running a new amp and headunit with the stock Speakers, or trying to limit running new wire to the doors but using the stock wireing. (I wouldn't do either personally, but this will definately work, and if your not looking for high end, it will probably work well. (Speed cable rocks)
Anyone know exactly where the Power wire runs from Battery to Engine? I thought mine ran down the middle of the car, but maybe I wasn't looking very hard.
As I read through this sticky, What it looks like your doing it either Running a new amp and headunit with the stock Speakers, or trying to limit running new wire to the doors but using the stock wireing. (I wouldn't do either personally, but this will definately work, and if your not looking for high end, it will probably work well. (Speed cable rocks)
Anyone know exactly where the Power wire runs from Battery to Engine? I thought mine ran down the middle of the car, but maybe I wasn't looking very hard.
Last edited by EmperorJJ1; Apr 13, 2008 at 05:33 AM. Reason: Automerged Doublepost
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Joined: 08-09-08
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From: Hartland, ME
So, I am installing a CarPC in my car, and the only point where I am nervous about is how to get the speaker outputs from the soundcard (converted to RCA's) into the factory amp.
I see adapters online that basically use the aftermarket speaker outputs to sedn signal to the amp. Is this a good idea? (I have a 4x25watt Pioneer amp to feed the factory amp if that is what I should do).
I would rather feed the amp more directly with RCA's, but I'm not sure what type of signal the factory amp expects to see.
I am leaving the speakers stock, and will be retaining the factory sub.
I see adapters online that basically use the aftermarket speaker outputs to sedn signal to the amp. Is this a good idea? (I have a 4x25watt Pioneer amp to feed the factory amp if that is what I should do).
I would rather feed the amp more directly with RCA's, but I'm not sure what type of signal the factory amp expects to see.
I am leaving the speakers stock, and will be retaining the factory sub.
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Joined: 12-01-08
Posts: 187
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From: Boise, ID
I just need a clarification on this please:
So this is only a problem for the front, you can simply run an LOC for the rear.
For the front, the general problem is that the crossover occurs inside the stock amplifier. If you use an LOC downstream of the amplifier, then you are only going to get the 'post-crossed over?' signal (i.e. you'd get a mids signal OR a highs signal).
Therefore you need to get a line in before the amp in order to get the full signal?
So this is only a problem for the front, you can simply run an LOC for the rear.
For the front, the general problem is that the crossover occurs inside the stock amplifier. If you use an LOC downstream of the amplifier, then you are only going to get the 'post-crossed over?' signal (i.e. you'd get a mids signal OR a highs signal).
Therefore you need to get a line in before the amp in order to get the full signal?
damn late ass reply but whatever...
there are various reasons on doign an amp bypass so it really depends on the goal. If u were addign a 4 channel amp and swapping speakers the goal would be to get LOC signal before the amp for both front and rear and tap the front woofer wires and rear wires to the 4 channel
Your thing about the signal is very close. The only signal thats filtered is the tweeter signal. so tapping that for anything is going to be useless.
Also i just thought about this. if ur running the stock HU and using an LOC before the amp ur signal is going to be very weak because of the stock decks line level outputs.
Ultimately like ive said before its really best to either leave it all or swap it all(regarding the midrange door speakers). nitpicking can be done but its a odd system and pretty crazy. I would be a post ***** if pioneer made **** easy
there are various reasons on doign an amp bypass so it really depends on the goal. If u were addign a 4 channel amp and swapping speakers the goal would be to get LOC signal before the amp for both front and rear and tap the front woofer wires and rear wires to the 4 channel
Your thing about the signal is very close. The only signal thats filtered is the tweeter signal. so tapping that for anything is going to be useless.
Also i just thought about this. if ur running the stock HU and using an LOC before the amp ur signal is going to be very weak because of the stock decks line level outputs.
Ultimately like ive said before its really best to either leave it all or swap it all(regarding the midrange door speakers). nitpicking can be done but its a odd system and pretty crazy. I would be a post ***** if pioneer made **** easy
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Joined: 04-22-09
Posts: 30
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From: Willowick, Ohio
Do u think the stock amp will be able to handle this?
http://www.crutchfield.com/p_1081052...2w.html?tp=111
http://www.crutchfield.com/p_1081052...2w.html?tp=111
Last edited by Nebs2021; Sep 20, 2009 at 10:50 PM. Reason: Automerged Doublepost
The question is not if the stock amp can handle a sub, its wether or not a sub can handle an amp.
Now that sub has a 125rms @4 ohm (per voice coil) power rating, the stock amp runs at 2ohms x2. If your just going to strait swap subs I would look for something that runs dual 2ohm voice coils.
Now that sub has a 125rms @4 ohm (per voice coil) power rating, the stock amp runs at 2ohms x2. If your just going to strait swap subs I would look for something that runs dual 2ohm voice coils.
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Joined: 07-14-08
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From: HBG PA
The question is not if the stock amp can handle a sub, its wether or not a sub can handle an amp.
Now that sub has a 125rms @4 ohm (per voice coil) power rating, the stock amp runs at 2ohms x2. If your just going to strait swap subs I would look for something that runs dual 2ohm voice coils.
Now that sub has a 125rms @4 ohm (per voice coil) power rating, the stock amp runs at 2ohms x2. If your just going to strait swap subs I would look for something that runs dual 2ohm voice coils.
It is both ways around
If the amp is per say 4 ohm stable and the sub is 2ohm ... the amp will not be able to handle that ohm load and potentially cause the amp to overheat and shut off
regardless
you should never try to use a stock OEM amp with an aftermarket woofer
you will not have great success
ps. impressive equipment list in your sig ... my shop has had great results with the hertz products excellent choice
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From: Cali
yea im with justy where is it... i was told when i swapped out my head unit that it was intergrated into the stock radio.. but my brother is telling me that its in the stock sub box... im hella confused and looking into putting in an aftermarket amp to push the sub better
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Joined: 03-24-08
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From: Fishers, IN
I'm currently in the process of replacing my OEM Amp and Speakers in my 2009 Cobalt, but keeping the stock H/U. Here are some wiring diagrams I found that are nice and easy to read!
AMP connector 1 - https://www.cobaltss.net/gallery/fil.../143419475.gif
AMP connector 2 - https://www.cobaltss.net/gallery/fil.../143418744.gif
AMP connector 3 - https://www.cobaltss.net/gallery/fil.../143419462.gif
Radio connector 1 - https://www.cobaltss.net/gallery/fil.../143281017.gif
Radio connector 2 - https://www.cobaltss.net/gallery/fil.../143386445.gif
I'll post some pics of the install when I'm done
Cleancut - take off the dash cover under the steering wheel. On the left side, right around where the trunk release button was, look straight back toward the firewall. It's right there. Detach the cable clips from the brackets. There are some small retaining clips that you might have to unscrew that grip these little brass knobs. Unscrew them and remove the clips. On mine I couldn't even reach 2 of the 3, but I found it didn't matter. I just removed the one I could get to with the screw driver. Push the amp upward from the bottom so the brass knobs slide up the slots and then push it back toward the firewall to disengage the brass knobs from the mounting plate. Now you can pull the amp out from underneath and unhook the cables.
AMP connector 1 - https://www.cobaltss.net/gallery/fil.../143419475.gif
AMP connector 2 - https://www.cobaltss.net/gallery/fil.../143418744.gif
AMP connector 3 - https://www.cobaltss.net/gallery/fil.../143419462.gif
Radio connector 1 - https://www.cobaltss.net/gallery/fil.../143281017.gif
Radio connector 2 - https://www.cobaltss.net/gallery/fil.../143386445.gif
I'll post some pics of the install when I'm done
Cleancut - take off the dash cover under the steering wheel. On the left side, right around where the trunk release button was, look straight back toward the firewall. It's right there. Detach the cable clips from the brackets. There are some small retaining clips that you might have to unscrew that grip these little brass knobs. Unscrew them and remove the clips. On mine I couldn't even reach 2 of the 3, but I found it didn't matter. I just removed the one I could get to with the screw driver. Push the amp upward from the bottom so the brass knobs slide up the slots and then push it back toward the firewall to disengage the brass knobs from the mounting plate. Now you can pull the amp out from underneath and unhook the cables.
Last edited by fryedaddy; May 24, 2010 at 01:22 AM. Reason: Automerged Doublepost
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Joined: 07-12-08
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From: Burbank, CA
i would definitely love to see an easy to read HOW - TO on this...
basically
How-to remove stock amp and head unit and replace with new amp/ HU.
of course, so lots of pictures...non of this some do this, some do that, you could possibly do this..
basically
How-to remove stock amp and head unit and replace with new amp/ HU.
of course, so lots of pictures...non of this some do this, some do that, you could possibly do this..
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Joined: 03-06-09
Posts: 27
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From: Davenport, IA
Okay. so I've replaced all 6.5", and 6x9 speakers in my car. Their impedance is 4 Ω's. I have also installed subs and a after-market head unit. Since installing these speakers, they don't seem to be as loud as the stockers (hardly any bass)
So I'm asking, do I need to perform this amp bypass, to have my head unit power my after-market speakers.
Finally as a result of doing this, the stock sub would no longer work, correct?
So I'm asking, do I need to perform this amp bypass, to have my head unit power my after-market speakers.
Finally as a result of doing this, the stock sub would no longer work, correct?