(!!!) 12AX7=ECC83 Mullard UK "long plates" with "D" getter used/50-60% (0.6/0.7ma Gm=900/1000 - low Gm) (mC1 series)
(!!!) 7025 RCA Beckman ribbed gray plates used/60% 1960's (Gm=1100/1300 and 0.5/0.7mA)
(!!!) 7025 RCA ribbed gray plates low hours/tests like new 1960's faded printing (Gm=1500/1800 and 0.9/1.3mA) (V1 guitar amp)
(!!!) 7025 RCA ribbed gray plates used/good 1960's (Gm=1350/1450 and 0.7/0.8mA)
(!!!) 7025 RCA ribbed gray plates used/good 1960's (Gm=1350/1600 and 0.6./1.1mA) (V1 guitar amp)
(!!!) 7025 RCA ribbed gray plates used/good 1960's faded printing (Gm=1400/1600 and 0.9/1.1mA) (V1 guitar amp)
(!!!) 7025 RCA ribbed gray plates used/good 1972 (Gm=1450/1400 and 0.9/0.8mA) (V1 guitar amp)
(!!!) 7025 RCA ribbed gray plates used/tests like new 1960's faded printing (Gm=1500/1500 and 1.1/0.9mA) (V1 guitar amp)
(!!) (Best Single 1966) ECC83=12AX7 Siemens Halske Germany NOS 1966 (162 Series) (Gm=1500/1600 and 1.0/1.1ma)
(!!) (Best Value Holland 1959) 12AX7 ADZAM Holland NOS 1959 large "O" getter halo (.8/1.1ma and Gm=1400/1600)
(!!) (Best Value Single) 12AX7 Telefunken Germany <> bottom ribbed plates used/good 1960 (0.8/0.8mA and Gm=1400/1400)
(!!) (Best Value Single) 12AX7=ECC83 Mullard UK copper grid posts used/good 1965 (Gm=1400/1400)
(!!) (Best Value Single) ECC83=12AX7 EI Yugo Telefunken smooth plates clone 1973 era branded Amperex NOS 1985 (1.2/1.2ma and Gm=1700/1800)
(!!) (Best Value Single) ECC83=12AX7 Tungsram Hungary 1980 era branded Amperex NOS 1985 (1.3/1.6ma and Gm=1800/1800)
(!!) (Good Value Single) 12AX7A GE NOS 1976 (0.9/1.3mA and Gm=1400/1800)
(!!) (Good Value) 12AX7 Siemens Halske Germany rebranded "BOGEN" used/good 1960 (161 Series) (Gm=1400/1500 and 0.8/0.9ma)
(!!) (Good Value) 12AX7A/7025 Sylvania used/good 1970's (Gm=2300/1900)
(!!) (Recommended Single) JAN-12AX7WA Sylvania NOS 1974 (Gm=1600/1700 and
(!!) (Recommended Single) JAN-12AX7WA Sylvania NOS 1974 (Gm=2100/2300 and 1.7/1.9ma)
(!!) (SINGLE) 12AX7=ECC83 Telefunken Germany <> bottom ribbed plates low hours/like new 1962 (Gm=1500/1500) (0.9/8ma)
