CDinMB
Active Member
Hi, new to the forum and McIntosh stereo. I have loved the sound of these amps since I was a kid and finally bought them. I am now finding my self rebuilding them almost immediately after purchase and have a question before I go any further.
Is there a preferred circuit design among the running changes for the MC30?
Here is why I ask. I am rebuilding the two MC30s due to one developing a loud pop on start up. This is my first time working on Mac amps and they are my personal units I want to keep forever, so I want to build them right. I decided to replace all the circuit components not just the power capacitors. I am not an amp design expert but I can follow a circuit and layout. As I dig into my amp's circuit and study the schematics I find my circuit doesn't appear anywhere in documentation, so I am assuming it is an older circuit. I am faced with the choice of replacing existing parts as is or rebuilding to the new circuit design in the docs. Replacing what exists is easier but is there a reason to change it? Since the number and value of the capacitors are different, I assume this will change how the valves behave and have some sonic impact. I have experience with old Fender tube guitar amps I own and I know changing component values can change tone. I have searched and read for a few days here on the forum and not found any discussion of the +/- of either circuit. Some pictures show people have units with the same 6 cap design in the signal path I have versus 7 in the newer circuit but I haven't found a discussion of the difference.
So for the Mac MC30 experts looking at my amp's circuit, should I rebuild it as is, or move to the newer circuit and cap values shown in the schematics?
Thanks for input, I am really at a cross roads and don't want to do this twice.
TIA
Carmen
Is there a preferred circuit design among the running changes for the MC30?
Here is why I ask. I am rebuilding the two MC30s due to one developing a loud pop on start up. This is my first time working on Mac amps and they are my personal units I want to keep forever, so I want to build them right. I decided to replace all the circuit components not just the power capacitors. I am not an amp design expert but I can follow a circuit and layout. As I dig into my amp's circuit and study the schematics I find my circuit doesn't appear anywhere in documentation, so I am assuming it is an older circuit. I am faced with the choice of replacing existing parts as is or rebuilding to the new circuit design in the docs. Replacing what exists is easier but is there a reason to change it? Since the number and value of the capacitors are different, I assume this will change how the valves behave and have some sonic impact. I have experience with old Fender tube guitar amps I own and I know changing component values can change tone. I have searched and read for a few days here on the forum and not found any discussion of the +/- of either circuit. Some pictures show people have units with the same 6 cap design in the signal path I have versus 7 in the newer circuit but I haven't found a discussion of the difference.
So for the Mac MC30 experts looking at my amp's circuit, should I rebuild it as is, or move to the newer circuit and cap values shown in the schematics?
Thanks for input, I am really at a cross roads and don't want to do this twice.
TIA
Carmen
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