transistor amp not working after shorting output

There's one piece of test kit I'd strongly recommend to any newcomer, a cheap Chinese-made component tester - I'll add a photo of one below. It should cost around €20. I use mine all the time, probably even more than my multimeter. The real beauty is that you don't need to know what a component is, which way round the pins go, whether a transistor is NPN or PNP - the tester will tell you all of that.
Testing a component out of circuit requires desoldering it. Desoldering components from PCB that are not damaged can pull the lands off the boards. It can also break leads off the component. I've done both. The forwards-backwards diode test on b-e and b-c can determine some of which ones are bad quickly. sg97 has already determined both 2n3055 are bad. Likely one or both driver transistors are too. Those tests are to be done.
After the absolute trash is gone, powering up through a light bulb, one can measure Vce on the transistors to determine which other ones are bad. <1 volt is bad. B-E <.6 volts is bad. Or find bad resistors, or find bad solder joints. This pcb has apparently been soldered by an amateur, which can cause bad solder joints.
 
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i found out that this is 46 ohm on top of two reversed diodes wtff
 

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Probably good, that 23, but measure them the same way you did with the big ones.
A small movie is always nice to follow.
I believe you have four of them. Take you time and make sure you remember where they were fitted.

Hugo