As it was talking about the amplifier, I saw that it said the tubes were KT66 and could "easily be swapped out for an 6L6, EL84, or 6V6...." That would require a new tube socket and set up for fixed or cathode biasing. Are sure you didn't mean EL34, instead of EL84, which takes the same tube socket?
Possible error on latest newsletter 4/15/16
Error message
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