Last month Thomas presented the 6GE5 compactron beam pentode elaborated about it’s usability as an output tube implemented in a single ended amp. He took the time and went through the compactron tubes in search for a suitable driver. And the luck winner is 6AG9 tube. The 6AG9 contains both triode and a pentode. With triode amplification factor of 39, this can be used would make in the role of 2 stage amp with transformer-, LC or RC coupling.
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