Dave M

I've had my 97 Trans Am for a number of years now, and I've never been happy with the stereo. A previous owner "upgraded" it by adding a huge amp and subwoofer, new head unit and XM Radio receiver. Investigation revealed he replaced some stock speakers and abandoned others. But all these upgrades worked and sounded like crap.

I know next to nothing about stereos and stereo wiring, and I'm not an audiophile so I don't need anything fancy. But I like to rock out to my tunes while I'm driving and would like to make something that works. I would have been happy with the stock Monsoon system.

I bought a fairly cheap new head unit on Amazon to give me USB capability, but I'd like to get the speakers back to something resembling stock, maybe a little upgrade. That's going to mean an amp. When I took the old head unit out I found a mess of hacked-up wires behind it. In the hatch, pulling the panels revealed a nest of wires and equipment that I don't know what it is. I'm afraid I'll need to rip it all out and start all over, wiring harness and all. I'm hoping someone can look at the pictures I took and tell me all is not lost... give some advice to get back to something that sounds good, but doesn't need to be top-of-the-line.

There's an album of pictures here with some descriptions of what I found. Anyone who can give me some advice would be greatly appreciated. I read the Monsoon FAQ, but I seem to be a little beyond that. Is this salvageable?

The album

Thanks,

Dave M

FullFlavorPike

Yup. That's a mess.

You could leave his crappy wiring in place, hide it as best you can, and just run new wires from your headunit to some speakers in all four corners. If you just use nice coaxials, you won't even need an auxiliary amplifier. Head unit power ought to be good enough.

If you want to restore the factory wiring, it's all color coded, and the colors are listed in the FAQ, and you could probably work through it. Maybe it looks like he used the factory wiring harness to bypass the factory amplifier, which sort of sucks for you going "back to stock."

Honestly, I would probably admit defeat and just rewire the stereo myself with aftermarket speaker wire under the carpets and panels. Probably absorb less of your time better spent doing other stuff.

383z

iTrader: (2)

If you make time you can figure it all out. I've been there too.

First, it looks like he didnt buy a harness to plug in the aftermarket radio and he just spliced everything to connect the radio. He saved $20.... The new radio will have to be contected the same way or a harness will need to be put back on which I would do to simply that mess.

Second, that thing by the amp is a capacitor.
https://www.crutchfield.com/S-2D9N1x...itors/faq.html

Last, I would start tracing all the wires and pulling the wires I dont need. Once you deep dive into the wires then you will start figuring out what goes where. I still dont know nothing about stereo systems, but I was able to figure out what goes where and what is needed. I pulled a TON of wires that I didnt need and that weighted a ton too.

The hardest part is pulling all the panels, carpet, and door panels amd putting it back on.
When you step back from this project it will look crazy like that long math equation in high school, but once you take a closer look it is easy to break down and understand.

JC316

iTrader: (1)

He did some good, and he did some REALLY bad. From what I can tell, he bypassed the monsoon and ran everything back to that amp via RCA cables, and then powered both the sub and the door speakers off from the single amp. That's a little unusual, typically you would have a 4 channel amp for the door speakers and then a mono amp powering the sub. The hatch speakers are rarely used by anyone that's gone aftermarket, I would continue to ignore those and leave them unhooked.

The odd thing is a capacitor, and you are correct about those being crossovers. You have a couple of options here. You could rip all of his stuff out and start fresh, running new wires to the doors and powering directly off from the head unit.

I would reuse his setup, remove the capacitor and the subwoofer since you don't like bass. Not sure what his speaker setup looks like, but I would get a nice set of Focal or Infinity component speakers with a proper crossover. That V12 is an Alpine amp, so it should be fairly good, run the speaker wires off from the amp, to a crossover and then to the doors and sail panels.

Along the way, I would shorten, or at least tape the excess wiring and tidy everything up. The dash harness is a lost cause, I would continue with his hacked up example and hide it.

WhiteBird00

iTrader: (4)

Actually, the dash harness is not that bad. It appears that only the brown (dash lights) wire was cut in the black half of the factory connector and the white half appears to be intact below the head unit shelf. That means that the OEM harness could be put back together by simply reconnecting the brown wire and removing/insulating the splices made to the other wires. Then a Metra 70-1858 harness adapter would allow you to plug in an aftermarket head unit without further destroying the wiring.

Unfortunately, they don't make the original Monsoon amp connector anymore and it looks like the previous owner did a butcher job by cutting the wires really close to the connector leaving no room to splice them back together. You might be able to find the connector on ebay or in a junk yard with enough wire to be able to reconnect. Monsoon amps can be had fairly cheaply (check out the for sale section here). But then you'd have to get all the correct speakers as well - probably not a worthwhile project unless you were doing a restoration.

As others have said, your best option might be to run your own wiring for a basic aftermarket setup with head unit, new speakers and an amp if you want more power than the HU alone.

biketopia

iTrader: (5)

Like the others stated, it kinda looks worse than it really is. I ran wiring to my door and sail panels on my 95 to power up the 4 speakers in it. Took about 2 hours start to finish, no carpet needs to come out, just the sill plate covers. If you're not using the sub box, any chance you'd be willing to sell it?

Dave M

Thanks for the replies, everyone. I thought I had enabled notifications on this post, but I guess I did not because I just happened upon these replies when I came in to ask another question. I believe that question has already been answered with a previous reply, so thank you.

What I decided to do was to rip out all the aftermarket stuff and basically start fresh and try to put the OEM equipment back in. I bought a Monsoon amp on ebay and a Metra wiring harness to try to get the dash wiring back to the way it's supposed to be. I'm still trying to find the connector that plugs into the Monsoon amp but I'm optimistic I'll find one on ebay. Once I see what kind of speakers he has in place, I want something that will work with the stock wiring and amp, but that is upgraded from stock. But for now I'm pulling everything out and already I can see this won't be as bad as I initially thought. I'll probably sell his old equipment to fund its replacement and maybe have some leftover for some go-fast parts. And on another note, I found out this car used to be plumbed for nitrous.

WhiteBird00

iTrader: (4)

When I said that they don't make the amp connector anymore, I was referring to Metra. I just looked up the original GM part number and it's still available. The part number is 12110115 and GM Parts Direct has them for only $6.37 (don't be surprised if their shipping costs more than the part - they're notorious for inflated shipping costs).

biketopia

iTrader: (5)

If OP has a junk yard or pick & pull close by that might be a good place to check for that connector.

Dave M

That's awesome news, thanks. Are you sure that's the right part number? GM Parts Direct says it fits a 2000 Deville. Will it come with wires on it to splice onto my existing harness? The picture seems to show it with wires, but there's not much detail. I'll have to call around to junkyards as well to see if I can pick one up locally to avoid the $14 they want for shipping.

WhiteBird00

iTrader: (4)

The part should come as a pigtail (connector plus wires). It is listed for a variety of GM vehicles so the wire colors may not match your application exactly but you can use the pinout diagram in the Monsoon FAQ sticky to match pin positions to the factory harness wire colors.

Dave M

Thanks, I just ordered it. I'll have to post some progress pics once I've got things cleaned up.

biketopia

iTrader: (5)

For what it's worth, most pig tales I've bought over the years from GM come with all white and or grey wires in them.

Spartan7

iTrader: (7)

Same here. OP, if you want to preserve as many of the stock uncut wires as possible, which just makes it easier on yourself, you can use a paperclip to depin the cut wires and swap over some good ones you get in the pigtail you ordered.

Dave M

Good tip, thanks.

Dave M

I've removed all the old gear from the car. Amp, capacitor, subwoofer, and about 100 ft of wire. I want to weigh it all; it's probably 20+ pounds of stuff.

The dash area looks much cleaner and easier to work on now that all the excess wires are removed:

https://imgur.com/a/frumw


I have new connectors to splice onto the hacked up harness. I also bought a used Monsoon Amp and a connector for that, so I'll be able to splice that back in too. I still have to decide what to do about speakers. I haven't exposed the ones in the doors yet. I may have to swap them out for ones that are compatible with the stock wiring harness.

And it turns out, when I was taking off interior trim panels, I found a literal rat's nest. Never what you want to find in your car:


https://imgur.com/a/2lGCY

I appreciate everyone's help so far. I may need some more advice when I get to the speakers.

WhiteBird00

iTrader: (4)

You can also remove the four other spliced wires in the photo (red, yellow, etc.). Get a Metra 70-1858 harness adapter to connect to your new head unit and it will simply plug in to the factory harness without needing any of those existing splices.

There are plenty of threads about replacement speakers for Monsoon systems that should give you some ideas when you're ready to replace them. Since it's a Firebird, you don't have the restriction of coaxially mounted components in the doors like Camaros do - you can get whatever component set you prefer because the tweeter is separately mounted. The Bazooka subs are a popular and relatively inexpensive choice for dual voice coil subs in the sail panels.

Dave M

I bought a 70-1858 and a 71-1858 to replace the factory wiring harness connector and to have a new adapter to the head unit.

Dave M

An update. I got the wiring in the dash straightened out and the new head unit hooked up, and it works. But right now I'm only getting sound from the 4 tweeters. I assume this is because nothing is going though the Monsoon amp yet. It looks like this:



The piece I ordered to replace the clip did not come with any lead wires. Any idea how I connect wires to it? Would it be better to try to repair the oem piece?




In other news, I found more wires snipped off. These were in the driver's side hatch area. Anyone know what the missing wires would go to?




Lastly, I've exposed all the speakers. It doesn't look like any of them are stock except for the ones in the hatch, which were abandoned. I don't know anything about speakers. Does anyone recognize them? Will they work when I put the wiring back to stock? Are they any good? The sail panel speakers used to have 4 wires running to them. Two of them were snipped off. Should I replace the sail panel speakers with ones that need all 4 wires if I'm trying to go back to something resembling stock? I haven't exposed the wiring for the front speakers yet, but I assume since the tweeter is separate that they'll still work? Any help is appreciated. You guys have been a big help so far.

WhiteBird00

iTrader: (4)

Yes, that's normal on a Firebird. The Firebird Monsoon system has the amp powering all the speakers except the front and rear tweeters so without a connected amp, you will only hear the tweeters. In Camaros, the Monsoon amp powers all speakers so you would have heard nothing.

You have a couple of options. You could get a pin removal tool (available at Harbor Freight or online at Amazon for just a few dollars) so that you can pull the pins out of the original connector without damaging them and then be able to extend the wires by soldering onto the cut ends. Or you could try to find a Monsoon equipped f-body in a junk yard and cut off the connector with enough extra wire to make reconnecting easier. You might even be able to find someone here who has replaced their Monsoon with an aftermarket system and would be willing to remove the connector from their car.

Hard to tell the wire colors but judging by the location it's probably the wiring for the optional CD changer. That would have dark green, dark green/white, black, black/white, brown/white, and a bare drain wire.

The sail panels originally had dual voice coil (DVC) subs which is why there were four wires on each. You don't actually need DVC subs but going with single voice coil would reduce your power output by half. There are a few brands that make DVC 6.5" subs but they aren't common. CDT is a quality brand and the Bazooka subs have been a popular and relatively inexpensive replacement. Avoid Pyle and Boss brands unless you can't afford anything else.

There are dozens (if not hundreds) of threads discussing Monsoon speaker replacements so a search should give you all kinds of options and opinions. The Monsoon FAQ sticky will give you details of the sizes and types of speakers needed. If you have the opportunity, it would be best to go to an audio shop (or Best Buy) and listen to some different speakers. For example, Infinity speakers are known to be very "bright" - to the point that some people say they make their ears bleed while others really like the brightness.