(!!!!!) (BEST HOLLAND PAIR 1961-1963) 12AX7=ECC83 Philips Miniwatt Holland NOS 1961-1963 (1.2/1.3ma and 1.3/1.3ma) 1-3% matched
(!!!!!) (Best Holland Pair) 12AX7=ECC83 Philips Miniwatt Holland NOS 1963 (1.0/1.1ma and 1.0/1.1ma) 1% matched
(!!!!!) (Best Overall Pair) ECC803S=12AX7 Telefunken Ulm Germany <> bottom NOS 1961-1962 perfect condition (1.1/1.3ma and 1.2/1.5ma) (Nagra, Lamm, VTL, Aesthetix, Diva)
(!!!!!) (Best Pair) 12AX7=ECC83 Telefunken Germany <> bottom smooth plates like new 1960-1962 era (1.0/1.1ma and 1.1/1.1ma) 1-3% matched
(!!!!!) (Best Tungsram Pair) ECC83=12AX7 Tungsram Hungary NOS 1980 (1.4/1.6ma and 1.4/1.6ma) 1% matched (same mA and Gm) (Audio Hungary A50i)
(!!!!!) (Best Tungsram Pair) ECC83=12AX7 Tungsram Hungary NOS 1980 (1.4/1.6ma and 1.4/1.6ma) 1-2% matched
(!!!!!) (Best Tungsram Quad) ECC83=12AX7 Tungsram Hungary NOS 1980 (1.5/1.7ma x 4 tubes) 1-3% matched quad
(!!!!!) (Best Tungsram Quad) ECC83=12AX7 Tungsram Hungary NOS 1980 1-3% matched (1.2-1.4ma x 4 tubes)
(!!!!!) (Best Value Single) 12AX7 IEC Mullard UK NOS 1965 copper grid posts (0.7/1.2ma and Gm=1400/1700)
(!!!!!) (Best Value Single) 12AX7 Mullard branded "M" UK used/good 1961 copper grid posts (0.7/.8ma and Gm=1400/1500) (161 series)
(!!!!!) (Recommended Pair) ECC83=12AX7 Hammond Holland low hours/test like new 1963 and 1966 (1.1/1.3ma and 1.1/1.3ma) closely matched
(!!!!!) (Recommended RCA Single) 12AX7A RCA CMI gray ribbed plates NOS 1968 faded printing (Gm=1600/1700 and 1.0/1.4ma) (CMI=Chicago Musical Instrument Co.)
(!!!!!) (Recommended Single 1961) 12AX7=ECC83 Mullard UK branded Motorola ribbed plates low hours/like new 1961 (161 Series) (1.2/1.2ma and Gm=1550/1550) 1% section balance
(!!!!!) (Recommended Single) JRP-12AX7 Raytheon Black Plates NOS 1962 (Gm=1750/1800) (1.1/1.5ma)
(!!!!) (2nd Best Raytheon Black Plate Pair) JRP-12AX7 Raytheon tall-ribbed "Black Plates" NOS 1962 (1.0/1.0ma and 1.0/1.1ma) 1-2% matched
(!!!!) (Best GE Single) 12AX7 GE NOS tall ribbed plates 1964 (1.0/1.1ma Gm=1500/1600)
(!!!!) (BEST HOLLAND PAIR 1961) 12AX7 Fisher Holland low hours like new 1961 (1.0/1.3ma and 1.1/1.2ma) 1-3% matched
(!!!!) (Best Holland Single) ECC83=12AX7 Philips Miniwatt Holland NOS large "O" getter 1959 (1.1/1.1ma Gm=1600/1700) 1-2% section balance
(!!!!) (Best Overall Single) ECC803S=12AX7 Telefunken Ulm Germany <> bottom NOS 1962 1-2% section balance (Gm=1800/1800) (1.6/1.7ma)
(!!!!) (Best Single) 12AX7 Telefunken Germany smooth plates branded DYNACO like new 1965 (Gm=1600/1800)
