aftermarket HU & stock amp/wiring/speakers

[TDS-94SSEi]

Hey All,

I spent some time searching the old posts, but can't seem to find my answer. I have installed an aftermarket HU in my '94 SSEi, and I used one of the adapters that plugged right into the stock in-dash harness. Reason for this was I didn't have the time or $$ to redo the whole system.

Back when I had the OE head unit in there, and could use the 'gain' slider, the system got pretty loud, with decent sound. After the new HU, I didn't seem to have as much 'punch' when the volume was turned up. I'm thinking that I probably am not getting anything from the stock amp, since now the slider doesn't have any effect on the sound output. I'll admit that I never really understood how the stock setup was configured, and where the amp fit into it. I could almost swear that I recall reading on here about someone that found a way to integrate the stock amp into a similar system. Is anyone aware of something like this, or am I just mis-remembering? I find the sound output as it's currently configured, to be kind of 'flat' and lacking dynamic lows and highs. But I remeber these same stock speakers sounding much fuller before the HU install. It's been this way for a while, and I would like to try and improve the sound now that i'm finding some free time to look into it again.

I hope to add an aftermarket amp and sub, to be fed via the RCA output from the HU some day. But I'm not looking for any top of the line system, just something that can drown out some road and wind noise in the warm weather months.

I'd be interested to hear from some of you that are knowledgeable in the OE system, to see if I'm even going to be able to do what i'm hoping, with the pieces I've got. Thanks!

[Shae]

I think I know what your problem is, on the adapter you used to connect your new stereo to the factory wiring, there should be a blue wire, if its not hooked up to the blue wire that comes off of the new stereo, the amplifier will not know when to turn on.

If you DID hook up this wire, and it still does not work, look behind the adapter, at the factory harness, and see if you can find a pink or darkgreen wire, and tie it into your blue wire from the aftermarket stereo, and that should work. Make sure you test the wires with a multimeter first, or else you could fry something.

hope this helps

[TDS-94SSEi]

I think I know what your problem is, on the adapter you used to connect your new stereo to the factory wiring, there should be a blue wire, if its not hooked up to the blue wire that comes off of the new stereo, the amplifier will not know when to turn on.

If you DID hook up this wire, and it still does not work, look behind the adapter, at the factory harness, and see if you can find a pink or darkgreen wire, and tie it into your blue wire from the aftermarket stereo, and that should work. Make sure you test the wires with a multimeter first, or else you could fry something.

hope this helps

that sounds right if I recall. Pretty sure I didn't put the HU's blue wire to anything, since I lost my motorized antenna years ago in lieu of a fixed mast. This was one of those issues that I always just thought I would get to, and here it is a couple years later and I'm still not done. But your guess does make sense, and to hear the systema as it currently is, it sure sounds as if there's no amplification beyond the hi-level output from the HU. I'll have to pull things apart and see if thsi does indeed look to be how mine is currently, but I think you're probably right.

So the theory here is, once the factory amp is 'on', it amplifies the hi-level output downstream of the HU and before the speakers, and the 'gain' slider controls the level of amplification, correct?

If that's the case, then adding a sub and dedicated amp fed by my RCA outputs should still work alongsde the factory wiring and speakers, right?

[Shae]

I think I know what your problem is, on the adapter you used to connect your new stereo to the factory wiring, there should be a blue wire, if its not hooked up to the blue wire that comes off of the new stereo, the amplifier will not know when to turn on.

If you DID hook up this wire, and it still does not work, look behind the adapter, at the factory harness, and see if you can find a pink or darkgreen wire, and tie it into your blue wire from the aftermarket stereo, and that should work. Make sure you test the wires with a multimeter first, or else you could fry something.

hope this helps

that sounds right if I recall. Pretty sure I didn't put the HU's blue wire to anything, since I lost my motorized antenna years ago in lieu of a fixed mast. This was one of those issues that I always just thought I would get to, and here it is a couple years later and I'm still not done. But your guess does make sense, and to hear the systema as it currently is, it sure sounds as if there's no amplification beyond the hi-level output from the HU. I'll have to pull things apart and see if thsi does indeed look to be how mine is currently, but I think you're probably right.

So the theory here is, once the factory amp is 'on', it amplifies the hi-level output downstream of the HU and before the speakers, and the 'gain' slider controls the level of amplification, correct?

If that's the case, then adding a sub and dedicated amp fed by my RCA outputs should still work alongsde the factory wiring and speakers, right?

Thats 100% correct! You will have to split off that blue remote wire though, to turn on your aftermarket amps, and your factory amp!

[dpcookson]

The factory rear speakers (6X9) are essentially a dual voice coil design, meaning there are 2 inputs per 1 speaker. As of right now, without the factory amp enabled, only one of the inputs (primary voice coil) is getting a signal. When you get the amp powered up it will sample the outputs of the head unit then send a separate amplified signal to the other input (secondary voice coil) of the rear speakers, giving you that added punch you are missing.

[TDS-94SSEi]

Awesome, Thanks to you both for the help. That is kind of what I thought was going on. Glad to hear I should be able to solve and also grow into the next phase of my sound system without too much hassle.

[TDS-94SSEi]

posting to wrap this issue up.

When I installed the aftermarket head unit, and used the wiring adapter to plug into the stock harness, there were no wires going to 3 of the wires in the factory harness end. Once I traced all of the power, ground, speaker wires, it told me that these last 3 wires must be for the factory amp. One larger-gauge pink wire, and a light and dark green. I tapped off the blue remote wire from the head unit, and attached it to the pink wire (actually guessed a little on that one, but it being bigger made me think power). Now i have regained the use of the 'Gain' slider, and in turn the factory amp for what it's worth.

Still nothing attached to either of the green wires in that particular harness. And sound didn't really increase like i thought it might, although the bass level does change when operating the slider. I found mention of these 2 green wires in another post, that they were part of the steering-wheel radio controls. That would make perfect sense to me, as they were running into the OEM radio. Guess there's really no need for these to be connected anymore without the stock radio in the car.

Oh, and found that my antenna connection had fallen out of the new HU. Replaced that and now I have regained the ability to tune Am stations, which I had lost. ( and not REALLY missed, to tell the truth, LOL).