Fault
Amplifier would not power up, customer reported the that the fuse in the connected power lead blew when switching on the Amplifier.
The Amplifier was connected to the light bulb current limiter.
The Amplifier was powered up and the bulb lit very brightly indicating a short circuit.
The Crown XLS series uses a switch mode power supply rather than the conventional Toroidal transformer.
Power supply circuit checked Q903 & Q906 IGBTs short circuit
HTJ20N6