Hello all, I have an old Marantz 2275 amp which has a hum in it, and I'm quite certain it's in the preamp power supply as the main amps are perfect when disconnected from the preamp section, however, they've packed things into that case pretty tight and if I had a schematic it would really help me to track down the possible sources before I go tearing through everything. I'm going to go out on a limb here and say that a cap probably fried, and second guess would be a rectifier diode. If i could get a schematic for pretty much ANY Marantz amp from that era (1970's) it would go a long ways already. Just love the sound of this thing when its running well
thanks
thanks