I build the MP573 and everything works fine, but I find the output quite noisy and at the same time it has a very high output level (compared to other Skulptor pre amps I have). The class A output stage BA283AM has the right bias, but I am wondering why this stage is amplifying the signal with at least 15 dB. I made the feedback resistor R63 lower, 1k, and the signal level and noise level indeed drop. Why is there so much gain in this stage?
