Smoke on my power amp


I was listening the music with the right speaker wire detached to listen to the left speaker alone. The speaker wire was still attached at the amp side. My preamp does not have the balance knob.
After 20 secs or so, there was a smoke on my power amp.
I quickly turn off the amp.
Once smoke comes, would it be safe to turn it on again? I wonder whether it is permanently damaged.
Is it not safe to listen to the music with the speaker wire detached from one speaker but still attached on the amp side?
My amp is Plinius SA 102.
Any comment?
thx


128x128ihcho
Two hours north of Detroit.
If the transistor can be easily replaced, I might try by myself.
Thanks for your comments.
If you can get the parts and want to try it yourself.

After detaching from the heat sink, first cut the leads near the body of the transistor and then desolder/remove one at a time. Use some solder wick to clear the through-holes. 

Cut the new device leads to the same length as those removed and form similar, then solder in place.

Looks real easy to do right from the top.
If the transistor can be easily replaced, I might try by myself.

Here comes another thread.

just spend the money and let those that know how to fix it do it and then you know it’s done right.
in the specific case of tube amps having output transformers
Fair enough!  (But we were talking SS...)  Also that is more an issue of disconnecting while playing, rather than "turn on with no load" - which are quite different.
Ihcho,
Have the transistors been destroyed? It’s really grainy from the photos;

Since many of them are connected in parallel they all experienced significant current ( if actually shorted at output), but due to device tolerances, in the event of a short, the devices and emitter resistor combinations with lowest resistance will go poof the fastest; the emitter resistors on all output transistors of the compromised channel should be checked as well because even small changes there can really affect the distortion profile of the output stage.

If this were my amp and such a thing happened I would probably end up rebuilding the output board; Pain in the ass yes, but then you have a factory speced unit once again.

Did you examine the speaker connectors for evidence of arcing ? Black carbon, deformed metal etc...