I've bought an used A-80 amplifier. The output transistors have been replaced and just to be sure I've checked the output stage bias current. The Sansui manual states the voltage drop on the emitter resistors (0.33 Ohms) should be 1.5 mV. I achieved that figure but at the very end of the adjusting potentiometer. My doubt is the following: 1.5 mV over 0.33 Ohms give me some 4.5 mA. I do believe this current is TOO small for the output stage but this is the the official word from Sansui.
The amplifier has a harsh sound and I don't have a scope to check whether it has crossover distortion.
Does anyone think the bias current should be higher. Let's say 40/50 mA?
Thanks
The amplifier has a harsh sound and I don't have a scope to check whether it has crossover distortion.
Does anyone think the bias current should be higher. Let's say 40/50 mA?
Thanks