Audio Systems: Blown Stereo Twice, pioneer radio, impedance inputs

Question
I read through 10 million post never finding an answer for my specific issue so here I am. I have a 96' ford probe and installed a new pioneer radio and while enjoying my music at a high level of volume it stopped working I mean sound stoped coming out of my front and rear speakers. My sub continued to work just fine but not front speaker sound. I installed different kind of pioneer that basically did the same thing. It's funny though I can turn it up real load and a little distorted sound will start coming out of the speakers. My sub is run through it's own amp but my front speaker are powered by the tuner. I'm thinking either I have a bad ground or my alternator is pumping out to much or too little power or the positive and negative connections to my speakers are not correct causing a short at high volume levels. It's not a factory alternator. The fuse is not blown. Thanks in advance.

Answer
Joseph,
The problem could be due to the original stereo system that uses an external amp. The head unit may be over loaded by the low impedance inputs to the factory amp and it is causing the output amps in the head unit to fail, or the factory amp has failed. If the Pioneer audio output is at speaker level and they are connected directly to the speakers the problem could be due to a lower than required speaker impedance, a crossed connected speaker feed/return or a grounded speaker wire/line.

TOM,
T&D ELECTRONICS
tdeser@zoominternet.net