@donvito The HD220 is entirely fixable. It’s loosely based on On Semi’s reference design for thermaltrak devices.
The old production non DG designated output devices are End of Lifed but new ones are available on Mouser or Digikey.
Unless your friends tech was the one who replaced the bridge while the output stage clearly had a thermal runaway and fried the whole board, an HD220 amp that pulls standby after warm up is absolutely fixable. It’s just a bit of work and Audio research just doesn’t want to go through the trouble.
The old production non DG designated output devices are End of Lifed but new ones are available on Mouser or Digikey.
Unless your friends tech was the one who replaced the bridge while the output stage clearly had a thermal runaway and fried the whole board, an HD220 amp that pulls standby after warm up is absolutely fixable. It’s just a bit of work and Audio research just doesn’t want to go through the trouble.