Hello. I have a probleme with amplifier mackie m2600. Chanel 1 was bad, i change all 16 output transistors and 8 drivers. Now he is ok, but 2 output transistors is very hot. I buy the transistors from Mouser. I don t know what could be the problem. Thanks.
The schematic https://forumpoweraudio.ro/download/file.php?id=1269&sid=21f29696cc578af9c87b8b32871c002e
https://imgur.com/a/hIPRigZ here is a picture with hot transistors and some voltage measure.
The schematic https://forumpoweraudio.ro/download/file.php?id=1269&sid=21f29696cc578af9c87b8b32871c002e
https://imgur.com/a/hIPRigZ here is a picture with hot transistors and some voltage measure.
Ensure you use te correct heat transfer paste and the fixings are the correct torque or they will not cool properly.
Thermal paste is ok. I looked through the thermal camera and the 2 transistors are extremely hot. You can't put your finger on them.
If 2 output transistors are hot and the others aren’t maybe the emitter resistors of the cool ones are open.
Try checking the bias of each output device by measuring across each emitter resistor. Perhaps you need to match the devices or at least change those two that are hotter with something closer to the rest.