How to deal with microphonic 300B tubes.

Hi Jeff. Interesting observations regarding the sonic differences between the Kron 300bxl and the Kron 842Hvd in the Cary. I would concurr with your findings exactly. The 842 is certainly warmer, more akin to the warmth of the WE300b however I think the 300bxl is the better fit for the 805. It does wonders for tightening up the rather ripe lower registers of the 805 particularly the midbass area,not to mention the gain in fine micro resolution as well as dynamic range. Interesting though..... these same characteristics are also very evident when used as an output tube in a 300b based set amp.