In response to a question from a club member, Mica said that the type of tubes used in an F-2B were 12AX7. We are not loyal to any particular brand. We pick whichever 1) sounds good and 2) fits under the shielding sleeve. She went on to say that if you're looking at NOS tubes, look for 7025, they were the good 12AX7. However, now, all the 12AX7 makers are only making the 7025 version, so the distinction is only valid when looking at the old stuff.
