It sounds like you have blown your Output amplifier MOSFETs (Metal Oxide Semiconductor Field Effect Transistors) You will see some components with metal tabs, these are some of those along with some secondary stage pre driver transistors also screwed to the metal case (heat sink). Ok you will need some pieces of equipment. First you will need a schematic of the unit (never work without a schematic), second you will need a volt ohmeter (yes I am old) you might call it a multimeter. Now this is the bare minimum of equipment you need. first open ope the scematic and find the main voltage rails and test points, these will be important as you traces the source of your problem down. I want you to take measure ments of the test points and compare them to the measurements in the schematic, the places where the diffences are dramatic are the places the problem may be. remeber take these measurements and compare them to the schematic and then try to isolate the problem down to the components that are truly bad. Also pick up a book on how to repair audio amplifiers. This is the best I can do over the internet, happy hunting my friend.
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