(!!!!!) (Recommended Single) ECC83=12AX7A Tungsram Hungary branded RCA NOS 1970's (Gm=1700/1900) (1.0/1.4ma)
(!!!!!) (Recommended Single) M8137=CV4004=12AX7 Mullard branded Philips box plates NOS 1966 (Gm=1500/1400 and 1.0/0.8mA)
(!!!!) (2nd Best Pair) CV4004=12AX7 Mullard NOS 1981 (0.9/0.9ma and 0.9/1.0ma)
(!!!!) (2nd Best Siemens Single) ECC83=12AX7 Siemens Halske NOS 1966 (1.0/1.1ma) (Gm=1550/1600)
(!!!!) (Best Holland Single) 12AX7A=ECC83 Amperex Globe Logo Holland ribbed plates NOS 1970 (1.4/1.4ma and Gm=1700/1800) 1-2% section balance
(!!!!) (Best Overall Single) CV4004=12AX7 Mullard box plates NOS 1971-1972 (Gm=1600/1700) (1.3/1.5ma)
(!!!!) (Best Pair) ECC83=12AX7 Tungsram Hungary branded IEC Mullard NOS 1982 (1.3/1.6ma and 1.4/1.6ma) 1-3% matched (high Gm)
(!!!!) (Best Pair) ECC83=12AX7 Tungsram Hungary branded IEC Mullard NOS 1982 (1.4/1.4ma and 1.4/1.4ma) 1-2% matched
(!!!!) (Best Pair) ECC83=12AX7 Tungsram Hungary branded IEC Mullard NOS 1982 (1.5/1.4ma and 1.5/1.4ma) 1% matched
(!!!!) (Best RCA 1955) 12AX7 RCA black plates "D" getter NOS 1955 (Gm=1800/2000 and 1.2/1.5ma) (rare tube)
(!!!!) (Best Siemens Single 1972) E83CC=12AX7 Siemens Halske NOS triple mica made 1972 printed 1976 (1.2/1.2ma) (Gm=1700/1700) 1% section balance
(!!!!) (Best Single 1961) 12AX7=ECC83 Mullard UK ribbed plates NOS 1961 (161 Series) (1.1/1.1ma and Gm=1600/1700)
(!!!!) (Best Single 1961) 12AX7=ECC83 Philips Miniwatt Holland 1961 large "O" getter halo NOS (1.8/1.3ma and Gm=2100/1700)
(!!!!) (Best Single) 12AX7 GE NOS tall ribbed plates 1964 (1.3/1.2ma Gm=1700/1700) 1-2% section balance
(!!!!) (Best Single) 12AX7WA Sylvania NOS 1970's (Gm=3000/3100 and 2.5/2.5ma)
(!!!!) (Best Single) CV4004=12AX7 Mullard box plates NOS 1981 (Gm=1500/1600) (1.1/1.4ma)
(!!!!) (Best Tungsram Single) ECC83=12AX7 Tungsram Hungary NOS 1982 (1.6/1.5mA and Gm=2100/2000) (high Ma and Gm)
(!!!!) (Best Value 1965) 12AX7 Philips Miniwatt Holland like new 1965 (Gm=1900/1700 and 1.5/1.2ma)
(!!!!) (Best Value 1965) 12AX7 Philips Miniwatt Holland like new 1965 (Gm=2000/2000 and 1.6/1.7ma) (Highest mA and Gm)
(!!!!) (Best Value Pair #1) 12AX7=ECC83 Telefunken Germany <> bottom branded GAP/R Computor tube <> bottom smooth plates used/good 1964 era (0.9/0.8ma and 1.0/0.8ma)