Disaster NEED HELP PLS!

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Disaster

Hi people, I am in urgent need of help before going mad!
This is the amp I’ve just made and it took me a whole week to do it and managed to make it working perfectly.
( http://www.ampslab.com/c300.htm )
I wasn’t so lucky the second time I hooked it up because as pumping up some music, the center tap wire (ground of amp) went loose and the thing just freaked out!
I switched of immediately and rehooked the ground properly, however only a loud buzzing sound was heard! A disaster!
Checked out the components, no components were carbonized.
Checked out two power transistors any hfe resulted to be fine (aprox150)
As a start I’m thinking of replacing all small power bjt transistors.
I’m not an expert in troubleshooting, PLS what is your opinion about the problem


Here below is a schematic of the amp with grounds illustrated with red boxes
 

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Keep in mind that a transistor that measures a normal hfe,

may be damaged (it has happened to me). Your desicion to replace small transistors is quite reasonable, as they are more commonly damaged in such situations. In a situation like this, where I couldn't find a solution, I simulated the whole thing, found voltages in different places in the simulator, and compared them with real life. Wrong voltages existed around a small signal transistor (previously measured with a normal hfe). When I replaced it everything was ok.
I am not a repairer professionally, so this approach may be wrong. It's just what I did. Anyone else with more experience please contribute. It may be even a passive component (capacitor perhaps), which would be very unfortunate, because I thing it will be much more difficult to find it.
 
Supply voltages seem to be fine.
+/- 72v before accident (without amp connected)
+/-70v after accedent (without amp connected)
dont know why this 2 volts drop, maybe filter electrolytycs had a hard time during the accident.

Do you think driving transistors have been damaged ? because I have 10 of them and they are quite costy. how can I check if the are fine or not ?
 
replaced all bjt transistors from the line shown back, amny of them seemed to be faulth after hfe check, however still somthing wrong !

Now i`m going to replace Q10 and Q12

Do you think that the new replaced components cab be destroyed in the falty circuit
 

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