1989 bose radio alternator noise in speakers
 

I just recently purchased a 1989 C4. DO NOT want to replace the factory speakers, but there is a loud pop when turning the stereo on and there is alternator noise coming through the front speakers. Im assuming its a problem with the integrated speaker amps.

If this is case...

1. WHere do I get rebuilds from
2. If it isn't the AMPS is there a noise filter in the system that may have gone bad?

Thanks,
Rob

99% it is the amps. I don't have a place to recommend to fix them, I can tell you when mine where bad 10 years ago it was expensive as hell to repair them. I spent minimal $ putting in 4 new speakers and a radio. I got a deck that matches the green lights on the dash and it doesn't look out of place at all. IIRC the capacitors go bad on the amps causing feed back. I still have my factory deck speakers and amps packed away in a box.

https://cimg4.ibsrv.net/gimg/www.cor...ba9b1300fa.gif
schematic
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Circuit board 134554
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Circuit board 136898
Had the same problem, one or more of the electrolytic capacitors are bad in one or more of the amps at each speaker. The capacitors are easy to replace. the capacitors get an internal short and bulge when they are bad I just replace all the capacitor and they work for a while. I have not replaced them for the last 10 years. I usually buy the parts from Digikey URL https://www.digikey.com/products/en/...-capacitors/58

I'll attach the schematics.

Ray

Best place to repair the amps is FACTORY CAR STEREO REPAIR http://www.carstereohelp.com/

Trust me on this - have used them several times on various Vettes. They will also talk to you about symptoms and have good guides online. They also don't sell you amps for other cars that fit but have a different sound stage.

Had amps rebuilt for my friends C4 ZR1 and my 95 coupe PERFECT RESULTS.

Thanks for the schematics and input. Much appreciated. I found a core set with four speakers and ahead unit im going to have refurbished and sent back and then get my installed set refurbished so I have backups.

Rob

I talked to them a few minutes ago, guy knows his stuff for sure. Thanks for the direction to them. I found a core set with head unit, two front speakers and the LH/RH rear speaker assemblies. Gonna send them to him for repair and then pull my units and send them for repair so I always have a backup.

Rob

Yeah I thought about aftermarket, but am very fond of the bose sound. I was able to find a full set of speakers/enclosures/amps for the car with a spare head unit as well.

Its not completely gone yet but im going to delay driving her a lot til I get the core set looked over and repaired as needed.

Rob

I've used Dr. Don's for my Bose head unit and I hear they also work on the amps.

Best advice in the thread!
I sent all four of my amps to them for rebuilding..... have worked great since.
I also have an '89 with the Bose system and had the same symptoms as the op highly recommended.