(!) (Recommended Single) 6EU7 RCA NOS 1970's (51/32 and 60/32)
(!) 12AT7 East Germany branded "M" Mühlhausen NOS 1970's (8.4/9.0ma)
(!) 12AX7=CV492 RFT East Germany 1970's like new (Gm=1500/1500)
(!) 12AX7A GE used/good 1981 (Gm=1150/1350, 0.6/0.8ma)
(!) 12AX7A GE used/good 1981 (Gm=1250/1250, 0.6/0.7ma)
(!) 12AX7A GE used/good 1981 (Gm=1250/1350, 0.6/0.8ma)
(!) 6BQ5 GE used/good 1960's (35.5ma)
(!) 6BQ5 Sylvania black plate used/good 1960's (51ma)
(!) 6EU7 RCA NOS 1970 era (51/32 and 52/32)
(Best Single) 6BQ5 Raytheon NOS 1960's (62ma)
(Best Value Pair) EL34 Mullard UK used/good XF2 single halo 1971 (74ma and 78ma)
(Read Review) 6SN7GTB GE NOS 1968-1974 (Schiit)
(slightly microphonic) JAN-5751 Sylvania NOS 1973 (2.0/2.3ma)
12AT7 East Germany branded "M" Mühlhausen NOS 1970's (7.2/7.6ma)
12AT7 East Germany branded "M" Mühlhausen used/tests like new stain on glass 1970's (9.4/9.6ma) (high Ma and Gm)
12SN7GTA GE branded Westinghouse low hours 1960's (7.0/7.4ma)
12SN7GTA Westinghouse black plates "O" getter NOS 1961 (9.0/9.8ma)
12SN7GTA Westinghouse gray plates "O" getter NOS 1964 (7.6/8.0ma)
311CH Cetron NOS in original box 1979 (100ma) (311CH is sub for 211H)
407B Western Electric NOS 1968 (50/26 and 51/26)
