Hope someone can help, I've got a 1988 IROC with the bose system in it. The problem I have is that the front speakers make noise but not a hum or buzz. Its kind of like a dull squeak that changes in freq, but is constant with the volume at any point. The drivers side speaker dosent sound very strong. The person before me who owned the car installed a pioneer 6 disc changer in the rear pit. The system dosent wire to any speakers though, its runs through a FM radio freq. The car only has 2300 miles on it, so the radio hasent had alot of use. Also the noise is there with the engine off or running. I dont think its an interferrance thing. Any help or advice would be good. Thanks

 

Wait...you have a car with 2300...or 23,000?? Either way, sweet

Anyway, when you say it changes in frequency, does it do it with the car off and/or does it change when you hit the gas/change rpm's/load. Also, does it only do it when your using the CD player or does it do it no matter what you use?

It sounds like a grounding problem, maybe head unit or CD changer related .

 

No you read it right, actually its 2,385 miles all original. As I said I don't spend a lot of time in the car! but sometimes I just sit in it in the garage and listen to the radio, sounds weird huh. It will make the noise with just the ignition in accessory position. If I turn the vulume down all the way the noise is the same but only from the front speakers. The engine dosent need to be running but will be the same if it is running. The cd changer is not hard wired to the speaker system, it runs through a FM modulator. I've got a service manual but these manuals say nothing about the Bose system.

 

One other thing, milage is 2,285. I just totally disconnected the cd player and this didnt change a thing! I'm starting to think it may me a amp or something like that thats out.

 

Well, that's a tricky one

I guess it might be coming through your front speaker wires from somewhere. Does it happen if your in accessory with the stereo off? If so, that would support the noise coming through the speaker wires theory.

Other then that, maybe your head unit is messed up. I had a pioneer do that to me, but it only happened with the car on, so I'm not sure that it would be something like that.

I'm not really sure what to tell you, maybe someone else has some more info on it.

 

Try another speaker, if not it then check th amp, by hard wiring a speakerto the radio. good luck

 

This may help someone out there. The delco bose system will not work with just any aftermarket speaker. Each speaker has a powered amp plugged into each speaker. There was a common problem with the front amps, the capacitors inside would go bad, infact some were bad the day they were installed new. Its very easy to remove the amps from the cased unit. I sent mine to a place called Precision radio they are located in San Antonio TX. They have over 25 years of experience in these systems. They are also very helpful in explaining just how to take the unit apart. But just about any noise or problem with these front speaker units can be because of a bad amp.

 

Thanks for the info, I trace down the loud tone noise to a bad amp in the front sail panel. But removing the carpet around the amp assembly would be a pain. If the capacitors are the reason, I probably replace the electrolytics first. I heard back in the 80s that those types of capacitors degrade over time.