#1
is 2 power valves arent matched, is it reasonable for one of them to have a brighter glow in the filaments inside the valve itself?
#2
if theres a slight difference it should be fine, but that tube will go before the other one does, which is why you should always get matched tubes, if you can adjust the bias for each one seperately i would try to get them to where they match as much as possible.
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