(!!!!) (Good Value Single) JRP-12AX7 Raytheon Black Plates NOS 1962 (Gm=1300/1600) (0.7/1.1ma)
(!!!!) (Good Value Single) JRP-12AX7 Raytheon Black Plates NOS 1962 (Gm=1500/1700) (0.9/1.2ma)
(!!!!) (Holland single 1958) ECC83=12AX7 Triotron Holland "long plates" with "D" getter halo like new 1957 (1.1/1.2ma and Gm=1700/1700)
(!!!!) (Read Review) 12AX7A=ECC83 Matsushita Japan NOS rebranded Raytheon NOS 1970 era (Gm=1800/1800 and 1.5/1.3ma) (similar to Mullard)
(!!!!) (Recommended Pair) 12AX7 Philips and Valvo Holland NOS 1965-1966 era (1.2/1.1ma and 1.3/1.2ma)
(!!!!) (Recommended Pair) 12AX7 Telefunken Germany <> bottom ribbed plates used/very good 1960 era (1.0/1.2ma and 1.0/1.1ma) 1-5% matched (highest mA and Gm)
(!!!!) (Recommended Pair) 12AX7=ECC83 Philips and Pope Holland NOS 1965-1967 (2.1/1.8ma and 1.6/2.1ma) (Highest mA and Gm)
(!!!!) (Recommended Pair) ECC83=12AX7 Tungsram Hungary branded IEC Mullard NOS 1982 (1.5/1.6ma and 1.4/1.7ma)
(!!!!) (Recommended Single 1955) 12AX7 BRIMAR England like new gray ribbed plates "D" getter 1955 (1.1/0.9ma) (Gm=1700/1500)
(!!!!) (Recommended Single 1957) 12AX7 BRIMAR England NOS gray ribbed plates "O" getter 1957 (1.3/1.2ma) (Gm=1700/1900)
(!!!!) (Recommended Single 1959) 12AX7 BRIMAR BVA England like new gray ribbed plates large "O" getter 1959 (1.1/1.0ma) (Gm=1500/1600)
(!!!!) (Recommended Single) 12AX7 Brimar BVA England narrow ribbed plates used/good 1959 (1.1/1.0ma and Gm=1450/1350)
(!!!!) (Recommended Single) CV4004=12AX7 Mullard box plates NOS 1971-1972 (Gm=1500/1500) (1.0/1.1ma)
(!!!!) (Recommended Single) CV4004=12AX7 Mullard box plates NOS 1981 (Gm=1500/1600) (0.9/1.1ma)
(!!!!) (Recommended Single) CV4004=12AX7 Mullard box plates NOS 1981 (Gm=1500/1600) (0.9/1.2ma)
(!!!!) (Recommended Single) ECC803S=12AX7 Telefunken Ulm Germany <> bottom gold pins NOS 1961 (1.3/1.5ma and Gm=1600/1800)
(!!!!) (Single) E83CC=12AX7 Siemens Halske Germany NOS 1976 (0.7/0.9ma and Gm=1400/1600)
(!!!!) (Slightly microphonic single) 12AX7=ECC83 Mullard UK branded Philips ribbed plates NOS 1962 (161 Series) (1.0/1.2ma and Gm=1600/1650)
(!!!!) (Slightly microphonic Single) CV4004=12AX7 Mullard box plates NOS 1981 (Gm=1400/1500) (0.8/1.1ma)
(!!!) (Best Single 1962) JHS-12AX7 Sylvania NOS 1962 (Gm=2600/2500 and 1.8/1.9ma)