I've stopped offering the R2.1 Preamplifier board upgrade for the first-generation McIntosh solid state amplifiers. I do install them however when I have an amp shipped to me for service. I stopped shipping the boards because most builders do not have the test gear to validate the performance.
What I miss are the photos of the installs I received from customers. What I don't miss however are the emails where the customer install required significant support either because they damaged the board or worse, the amplifier due lack of experience, short-cuts or incompetence.
I still get requests for the boards and, on occasion, relent. I shipped a bare board to a customer for his MC2105 along with a parts list and he did a beautiful job installing it!
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Customer install of MA6100 power supply board.
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