'92 Sc400 - Problem With Amp Or Speakers?

[gllexus]

I have just purchased a used '92 SC400. I recently noticed that the front driver's side speaker(s) and the rear passenger speaker(s) do not work properly. I tested this by using the balance and fade buttons. I do get muffled, low-volume sound from both the front driver and rear passenger areas, but not much. The front driver sounds like muffled low volume high freq sounds with very little if any bass sounds. The rear passenger sounds like muffled low volume low freq (bass) sounds with very little if any high freq sounds.

The front passenger speaker(s) sound fine and the rear driver speaker(s) sound fine, although at higher volumes (say turning the volume knob to 50% or higher), certain low freq. sounds cause it to rattle a bit. Is that normal?

Any help would be greatly appreciated.

Thank you!

-Gene

P.S. Great forum!

[JDOwen2]

From what I have read on the subject, I'd say your amplifier is bad. You could check out the connectors under the rear seat and also at the amp for corrosion.

[gllexus]

Are there any tutorials anywhere on how to do this? I think I have read that the amp is below the CD changer in the trunk. Do I start there or do I have to test things at each speaker?

Thanks in advance.

-Gene