(!!!!!) (2nd Best Single 1958) 12AX7=ECC83 Mullard UK "long plates" NOS 1958 (1.3/1.4ma) (f91 series)
(!!!!!) (Best Holland Pair 1967-1968) 12AX7=ECC83 Philips and Philips Miniwatt Holland ribbed plates "O" getter halo NOS 1967-1968 (1.3/1.5ma and 1.4/1.6ma) (close Gm)
(!!!!!) (Best Mullard Pair) 12AX7=ECC83 Mullard UK ribbed plates NOS 1970-1974 (1.2/1.3ma and 1.2/1.1ma) (same Gm)
(!!!!!) (Best Overall Single 1957) 12AX7=ECC83 Mullard UK "long plates" NOS 1957 (1.3/1.3ma) 1% section balance (mC1 series)
(!!!!!) (Best Overall Single 1958) 12AX7=ECC83 Mullard UK "long plates" NOS 1958 (1.2/1.2ma) 1% section balance
(!!!!!) (Best Pair #1) 12AX7=ECC83 Telefunken Germany <> bottom ribbed plates low hours/test like new 1960-1961 faded printing (1.0/1.2ma and 1.1/1.2ma) 1-2% matched (phono grade)
(!!!!!) (Best Pair 1960's) 12AU7 Mullard UK NOS 1965-1966 same build (10.2/12.4ma and 10.6/12.0ma) (Rogue, Hovland, Audio Note)
(!!!!!) (Best Siemens Pair 1972) E83CC=12AX7 Siemens Halske Germany NOS triple mica 1972 printed in 1976 (1.0/1.3ma and 1.1/1.3ma) (best in phono stages and high end preamps)
(!!!!!) (Best Single) ECC82=12AU7 Telefunken Diamond Bottom <> smooth plates NOS 1970 (14.4/14.2ma) (Highest mA and Gm)
(!!!!!) (Best Tungsram Single) ECC83=12AX7 Tungsram Hungary NOS 1980 (Gm=1900/1900) (1.2/1.5ma)
(!!!!!) (Best Tungsram Single) ECC83=12AX7A Tungsram Hungary branded RCA NOS 1970's (Gm=2000/2300) (1.7/1.8ma) (Highest mA and Gm)
(!!!!!) (Nice Single) ECC82=12AU7 Telefunken Germany <> bottom ribbed plates used/good 1957 (8.5/8.2ma)
(!!!!!) (Recommended Pair) JAN-CTL6SL7WGT Tungsol NOS brown base gray ribbed plates 1961-1965 (2.1/2.2ma and 2.1/2.3ma) (low noise - very smooth sound) (phono grade)
(!!!!!) (Recommended Single) ECC83=12AX7A Tungsram Hungary branded RCA NOS 1970's (Gm=1700/1900) (1.0/1.4ma)
(!!!!) (Best Pair 1960 era) ECC82=12AU7 Telefunken Diamond Bottom ribbed plates like new and NOS 1957-1960 (14.0/11.2ma and 11/12.5ma) (Highest mA and Gm)
(!!!!) (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 Single 1961) 12AX7=ECC83 Mullard UK ribbed plates NOS 1961 (161 Series) (1.1/1.1ma and Gm=1600/1700)
(!!!!) (Best Single) ECC82=12AU7 Telefunken Diamond Bottom ribbed plates like new 1960 (10.6/10.2ma) (same Gm)
