This old good amp with 2SA1103 / 2SC2578 pairs had no sound at all. No relay click. There're ±47V OK. Seemed like a protection, but not clearly stated.
I check power transistors output and at one channel there's high DC, so yes, it's a protection.
No transistors shorted. In this case, Q301 solders are clearly broken due to long term thermal expansion/contraction. It has a long aluminium heatsink, and Q301 and Q401 are at both ends, so they suffer from dilatation differences between heatsink (where they're screwed) and PCB (where they're soldered). This is the A-B-C of vintage amp repair.
Ressolder Q301, Q401, IC301 and IC401 (preamp ICs). That's all.
Amazingly powerful, great bass.
I check power transistors output and at one channel there's high DC, so yes, it's a protection.
No transistors shorted. In this case, Q301 solders are clearly broken due to long term thermal expansion/contraction. It has a long aluminium heatsink, and Q301 and Q401 are at both ends, so they suffer from dilatation differences between heatsink (where they're screwed) and PCB (where they're soldered). This is the A-B-C of vintage amp repair.
Ressolder Q301, Q401, IC301 and IC401 (preamp ICs). That's all.
Amazingly powerful, great bass.
what did we say about hoarding too much stuff and depriving others of them?! *cough* socialism *cough* lol! 
