GTA Stereo upgrade - Wiring.

Hi all,

Today i have been busy replacing the Ancient phillips radio setup in my GTA.

I managed to get a Alpine DVA-9861Ri off ebay for just over £100. It was still brand new and unopened !.
Retails for over £300.
This is a DVD based head unit, so can provide video if required, or store many hundreds of MP3's on a 4gb DVD disc.

I removed the GTA's metal frame that supports the radio, and fliped it upside down. So now the single DIN slot is at the bottom. Since i wanted my stereo at the bottom. I then used a Double DIN blanking plate to blank off the large hole.
I plan to put a quality boost gauge, and maybe a clock in this at a later stage.

Anyway, i printed off the stereo wiring guide from the tech section, only to find out the wiring in my 88 GTA is different.
So with the aid of a multimeter, and a 9v battery, i set about working out what was what.
I used a 9v battery to check the polarity of the speaker cables. On correct polarity, the speaker will push out. You only need to get the polarity wrong on one speaker and the whole system will sound rubbish. Since 1 speaker will be sucking in, while the others push out on bass notes.

So for info, here is the Stereo wiring information for a 88 GTA.

White Block Connector. Front Right Speaker.
------------------------------------------------------------------
White = -ve
White / Red dash = +ve

Yellow Block Connector. Front Left Speaker.
-----------------------------------------------------------------
Purple = -ve
Purple / Red dash = +ve

Larger Black Block connector. Rear Speakers.
--------------------------------------------------------------------
Purple / Yellow dash. Rear Right. = -ve
Purple / Green dash. Rear Right. = +ve
White / Yellow dash. Rear Left. = -ve
White / Green dash. Rear Left. = +ve

Red Block Connector. Power supply.
-----------------------------------------------------
Black. Permanent Ground.
Yellow. Switched Ignition 12v. +ve


There was no heavy duty continuous 12V supply behind the radio, So i used some heavy duty Amplifier cable to provide a direct supply from the battery. Since my Alpine head unit needs a 20amp supply.

Rather than using connectors, i soldered all the connections, and then shrink wrapped them.

I fired up the head unit, and WOW!. Holey smoke. Its loud.
I was going to replace the factory speakers in the doors and rear. But to be honest now i dont see any point. The bass is wicked. Very punchy. And the clarity of music is great even at high volume. Got to say im impressed considering they are 20yr old paper cone speakers.

Did not manage to get any pics done, will try to take some when its light tomorrow.

Also, i re-carpeted the rear Engine cover panel today, with new Black carpet. Got to say it does look smart !.

Did the original stereo work perfect,even on Fm...

No, it was all dead.

Did not even bother trying to get it working, since i wanted to fit a modern unit.

Hi Paul,

I thought you might be interested in these pics that I did for a fellow member with a 88 Alp. Clearly I have taken the info from the manual (and we all know that anomalies do crop up with these circuits).
From the circuit, which I have just checked again after your posting, either the diag is wrong for the front speakers (the rear ones are fine) or there may be a prob on your wiring, so it may be worth checking if you want to be sure, but if you find yours is right, please let me know so as I can amend my diags.
Hope this is of interest to you

Hi Jon,

Well that diagram does not match my 88 GTA.

My wiring is as above. Plus mine did not have a permanent 12v feed.
So i had to fit one myself. But that was probably a good idea anyway given the 4x 60watt output of my Alpine head unit,

Like i said, i confirmed all my speaker wiring with a pp3 9v battery. And removed all the speaker covers so i could the resultant action on the speaker cone.

Seems that they changed things on these cars pretty much on the fly !.

Continuing on this thread.......

After using my new Alpine head unit for a few days i realised it was actually quite easy to reach the limit of the 20yr old paper speakers..
So im looking at upgrading.

I have a full spare set of Door cards that i believe came from David Gentlemen. They have been re-covered, and opened up to accept 20cm speakers.
Ive allready found some nice Infinity 20cm 8" speakers that would do the job.
But im wondering about the rear speakers. From removing the covers and trying to examine the availible space, it appears they will have to stay the same 17cm ?
Has anyone managed to fit larger speakers in the rear ?.

Im also looking at Subwoofer options. But at present the only thing that would seem suitable would be a slim 10" active suboofer package.

Like this >>



Interested in hearing all your thoughts........

I have fitted these at work, they are a copy of the Focal product. They are very good value for money and give you a wormer richer sound. Added to a good set of component speakers and a good head unit, it will be more than a match for an audi bose system!! You will have to use some dynamatt (sound deadining) on the door speakers to stop vibrations.

I've just finished with upgrading my stereo. I have fitted an Alpine W202R double din DVD stereo, Pioneer speakers in the front, Sony's in the back (same size) and have also added a Kenwood 150W Subwoofer and an Alpine Ipod cable into the central storage box. The sub is meant to fit under the seat but doesn't as there really isn't much room under the A610 seats. Overall, the system sounds fantastic now although it wasn't an easy job. The Sub is fitted behind the drivers seat and can easily be removed if I had a passenger although the only passengers that can sit behind me are kids anyway (as I'm tall)!

Here's a few pics..

I was thinking the same thing.
Either leave it on the rear floor, or possibly..... Somehow attach it to the top of the rear transmission tunnel. Thus the seats would still be usable.

I'm lucky in that I don't really take too many rear passengers out and as long as they keep there feet off the sub there is no problem.

I did think about putting it in between the rear seats on the tunnel but it's not a great place from a security point of view (it's completely hidden behind the seat on the floor) and you also have to consider where all the wiring would go.

Well ive just finished re-carpeting my spare door cards.
And fitting some brand new 8"Pioneer speakers.

I think they look pretty smart !.



Tomorrow "Weather permitting", i shall be fitting them. And installing some new 6.5" Pioneer speakers in the rear.
Cannot wait to hear the sound quality improvement.

New door cards installed today, together with the 8" Pioneers.
And installed 6.5" Pioneers in the rear complete with crossovers and separate Tweeters mounted high in the corner of the rear window.

Sounds superb !.

While the door cards were off, i took the oppertunity to oil the window mechinism with engine oil. Now they wizz up and down quite speedy.

Good work there paul, the pioneer's arnt bad at all, looks good bud. Bounus about the windows too.

Yes im pleased with the Pioneers.
I was considering Infinity speakers since they also do a 8" speaker, but managed to get all 4 pioneers for £95 inc Del. Thought that was a pretty good deal.

Are you still going to have a subwoofer in the system or stay as you are?