2sc5200 and 2sa1943?

[adobetoo]

I have just replaced two pairs of Toshiba's 2SC5200 and 2SA1943 Transistors in a amp module in a power DJ speaker, After doing so the amp now hums and the transistors get extremely hot. What could be causing this? Could it be I have been sold fake transistors?


Adobe.

 

[jalou1995]

lot of fators to be considered, check the other parts esp caps, diodes and trannies.

 

[ostripper]

Blown OP's, usually = blown drivers as well.
Hum is loaded down power supply ???
OS

 

[AndrewT]

back off the output bias current to zero.
plug in the amp via a bulb tester to the mains.
Tell us if the bulb lights up.