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Topic: Aftermarket head unit with stock premium sound amp and eq? (Read 4187 times) previous topic - next topic

Aftermarket head unit with stock premium sound amp and eq?

So I'm thinking of installing the new head unit I got for Christmas with the stock premium sound amp and eq. The unit I have in the car right now has a metro harness to bypass the stock amp (which is unplugged). Following this diagram: http://www.foxthundercats.net/tech/aftermarketpremweq.pdf it looks like all I have to do is plug the stock amp and eq back in, make the connections from the headunit wiring harness to the factory plug, and then wire in two RCA jacks. I had a question on the RCA jack wiring though. It looks like the positive (center) of the right RCA jack goes to the pink wire with the light blue stripe, the positive (center) wire from the left RCA jack goes to the pink wire with the light green stripe, and then both negative (outer) wires go to the black wire with a white stripe? It also looks like the ground wire for the head unit gets connected to the big red wire that used to ground to the back of the stock head unit?
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Aftermarket head unit with stock premium sound amp and eq?

Reply #1
So I took a look at the wiring in the car (factory premium sound with EQ) and it looks like I should be able to tap into everything without cutting up the factory harness. I found the red wire that was unconnected to anything that the head unit grounds to. I did find a black wire that is unconnected to anything. That wire should be for the EQ right? I'm not sure where to connect it to the EQ but I think the lug on the right in this picture is the correct spot. Am I right or not?
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Aftermarket head unit with stock premium sound amp and eq?

Reply #2
Yes that lug is the ground for the EQ. I wired the head unit up per the diagram from Thunderchicken's site and it works great!

If you want to see it working go here: http://www.foxtbirdcougarforums.com/showthread.php?32806-Factory-graphic-equalizer-working-with-new-JVC-head-unit.&p=376574#post376574
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.


Aftermarket head unit with stock premium sound amp and eq?

Reply #4
I have used the factory EQ a couple times, but I never tried to use the factory amp.

I do love they way your greens match, sir.
CoogarXR : 1985 Cougar XR-7

Aftermarket head unit with stock premium sound amp and eq?

Reply #5
I want to keep the factory head unit, and upgrade the premium sound amp.:crazy::crazy::crazy:

I know, Im sick.
Mike

Aftermarket head unit with stock premium sound amp and eq?

Reply #6
The factory amp actually sounds good to me. Granted it's only 80wats but it thumps a little, which is good enough for me.

The JVC head unit I used has a display that changes color. It has 30 something choices. It's great for color matching to the rest of the dash.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Aftermarket head unit with stock premium sound amp and eq?

Reply #7
Bumping a VERY old thread.....

The Fox Thundercats link is now defunct....  Anyone have the info?????
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!

Aftermarket head unit with stock premium sound amp and eq?

Reply #8
If anyone plans on converting the stock head unit connector to RCA connectors the positive (center) of the right RCA jack goes to the pink wire with the light blue stripe, the positive (center) wire from the left RCA jack goes to the pink wire with the light green stripe, and then both negative (outer) wires go to the black wire with a white stripe. That's pretty much all that's required to convert the factory Premium EQ head unit plug to RCA preouts for an aftermarket head unit.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Aftermarket head unit with stock premium sound amp and eq?

Reply #9
Reason I'm asking is due to the "interesting" things I found behind my dash.....

I've always had the non-premium head unit.  I ALSO have the factory EQ and amp.  They work with the non-premium head unit in my car......


I know, I know; it's not supposed to.... 

Long story short, I've had some inspiration to do something with regards to my sound system in the car and before I tackle it I have to figure out just what the hell was done to this car that makes this stereo work with the EQ/amp....
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!

Aftermarket head unit with stock premium sound amp and eq?

Reply #10
Quote from: V8Demon;467697
Bumping a VERY old thread.....

The Fox Thundercats link is now defunct....  Anyone have the info?????

Dang, I saw this too late...Carm's site is still on the server, actually:
http://foxtbirdcougarforums.com/foxthundercats/samscars.htm

Aftermarket head unit with stock premium sound amp and eq?

Reply #11
Thanks.  Looks like they may not have hacked too much from what I'm reading and what I can see behind the dash.....  Now I need the EVTM for a mid 90's Probe....
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!

Aftermarket head unit with stock premium sound amp and eq?

Reply #12
IIRC the wiring for the non-premium sound stereo is in the dash. There is an extra connector on my car for it. So basically my car has 3 stereo connectors: the two for the premium sound system (head unit and EQ) then a separate one for the non-premium system. The connector for the non-premium head unit will work if you unplug the factory amp in the trunk.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Aftermarket head unit with stock premium sound amp and eq?

Reply #13
Keeping the factory amp....  Non premium plug is there.
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!

Aftermarket head unit with stock premium sound amp and eq?

Reply #14
Quote from: V8Demon;467697
Bumping a VERY old thread.....

The Fox Thundercats link is now defunct....  Anyone have the info?????


If it helps, here is the pdf file from the first post.
1985 Mercury Cougar XR-7 - 5-speed 
One of 1,246 built