Expert: Cleggsan - 5/14/2010

Question
My Pioneer amplifier(model SA-710) occasionally makes a loud popping sound. When this happens no other sound comes from speakers just the loud pop then split second of silence then back to normal. It is very random. I've tried different speakers but made no difference.
Is my amplifier fixable?

Answer
It has nothing to do with the speakers.

There are two possibilities that come to mind:

ONE:  Outside interference such as when the furnace or refrigerator comes on; it sends a pulse that gets into the amplifier causing the snap or pop sound.  This can be improved by plugging in to another outlet that is on a different circuit in the house.

TWO:  One of the electrolytic caps in the power supply or output stage is breaking down at random intervals. This is due to the age and gassy condition of that component.  Replacing it would solve the problem in this case.  They are not expensive nor difficult to replace but one must learn which one is the cause and how to get it out.  For that you may need an audio technician - which is an easy job for one so trained.

Let me know if there is more to the story.