I have 3 pair of Telefunken Dynaco branded 12AX7 tubes with <> Diamond logo bottom that I removed from a Dynaco PAS preamp and Dynaco FM-3 tuner.
Minimum value: 850
I tried to match them as close as possible on my Hickok tube tester and they all are very strong tubes.
1 pair tested 1600/1800 and 1600/2000
1 pair tested 1600/1700 and 1500/1500
1 pair tested 1700/1600 and 1700/1900
$65 per pair or $180 for all 3 pairs.
