I just purchased a MC250…. This is my first McIntosh amp.
When checking the voltage on the input section printed circuit board I noticed that the voltages at C55 and C56 where at +/-20V instead of +/-15V per the schematic.
I changed R111 and R112 from 3.3K to 5.6K to get the correct voltages
It looks like the input section uses 4.4mA. R111 and R112 now drop about 24.6V (5.6K * 4.4mA= 24.67V)
The schematic I have is for PCB 043-795 My amp uses PCB 044-557
Does anyone have a schematic for PCB 044-557?
Does this fix make sense?
Thank You
When checking the voltage on the input section printed circuit board I noticed that the voltages at C55 and C56 where at +/-20V instead of +/-15V per the schematic.
I changed R111 and R112 from 3.3K to 5.6K to get the correct voltages
It looks like the input section uses 4.4mA. R111 and R112 now drop about 24.6V (5.6K * 4.4mA= 24.67V)
The schematic I have is for PCB 043-795 My amp uses PCB 044-557
Does anyone have a schematic for PCB 044-557?
Does this fix make sense?
Thank You
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