Charles Angelich wrote in a message to All:

 CA> Along with the new-to-me PB machine I was given two amplified
 CA> computer speakers, Jenson no less.

 CA> They worked great the first night but the next day while moving
 CA> them to my 'main' machine I goofed. They hadn't given me the 'wall
 CA> wart' and I had used a 9v even though the back of the
 CA> speaker had 15v marked on the power input socket. It worked and
 CA> worked well. When I moved them I already had a 12v wall wart
 CA> plugged into the power strip so I plugged _that_ one in instead of
 CA> the 9v. It hummed with the switch turned off so I
 CA> immediately unplugged it. Not soon enough apparently. The left side
 CA> speaker only clicked for awhile then stopped and would do nothing.
 CA> The right side works but the left seems to be fried?  

 CA> I really don't understand why since the 12v was less than the 15v
 CA> marked on the speaker containing the amplifier? 

Sounds like it was the wrong polarity,  is this possible?

 CA> Really bummed me out they were nice! I've been brooding since I did
 CA> this. I can't really be angry with myself since I could've tried
 CA> the 12v first and never even had a chance to know they worked 
 CA> (which might've been better if I thought they were already 
 CA> broken?). Bummer, bummer, bummer! 

I can relate.

Fortunately,  most of this stuff is in a single chip these days,  not like
it used to be.  Open the bad one up,  and see if you can spot something
that's obviously cooked.  Maybe it's the chip,  maybe an electrolytic
capacitor or somesuch.  Probably not much,  as whatever it was that failed
took care of the voltage that would've damaged other stuff if the one part
hadn't soaked it up...

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