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Did you figure the amp out?
I admire your guts to tackle such a complex amp with not test instruments to speak of. But I am afraid you introduced more problems then resolved with your ill advised technique. By pulling all the transistors to check out of circuit you have introduced dozens of possible new problems that are harder to trace. Don't pull anything out until you determine a reason. The voltages on a transistor in a live circuit will tell you all you need to determine if it functioning, pulling it test little except junction drop with a constant current source across it. If you value the amp, put everything back, even the original caps in there original positions. The odds of putting all those signal transistors back in correctly unharmed is actually poor. Take the amp to a tech who has the test gear needed to evaluate the problem. It will likely save the amp.
The distortion sound was like breakthrough distortion, with only peaks turning on the current devices in the output. You are also working with a no-no condition of using a load on a defective solid state amp. Your heart is in the right place but you are doing everything to ensure an unhappy ending. If you had a scope you could see, without a load whether the waveform got better with no load. I suspect it does to a degree, indicating a problem fairly late in the amp signal flow. A level shifter or constant current source would be suspect but with your test method you are not going to find such a dynamic problem, that depends on the circuit to be live to duplicate the problem.
Good luck
I admire your guts to tackle such a complex amp with not test instruments to speak of. But I am afraid you introduced more problems then resolved with your ill advised technique. By pulling all the transistors to check out of circuit you have introduced dozens of possible new problems that are harder to trace. Don't pull anything out until you determine a reason. The voltages on a transistor in a live circuit will tell you all you need to determine if it functioning, pulling it test little except junction drop with a constant current source across it. If you value the amp, put everything back, even the original caps in there original positions. The odds of putting all those signal transistors back in correctly unharmed is actually poor. Take the amp to a tech who has the test gear needed to evaluate the problem. It will likely save the amp.
The distortion sound was like breakthrough distortion, with only peaks turning on the current devices in the output. You are also working with a no-no condition of using a load on a defective solid state amp. Your heart is in the right place but you are doing everything to ensure an unhappy ending. If you had a scope you could see, without a load whether the waveform got better with no load. I suspect it does to a degree, indicating a problem fairly late in the amp signal flow. A level shifter or constant current source would be suspect but with your test method you are not going to find such a dynamic problem, that depends on the circuit to be live to duplicate the problem.
Good luck
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