(!!!!) (Best Value Single) 12AX7 Telefunken Germany <> bottom smooth plates branded GAP/R Computor tube like new 1964 (Gm=1700/2000 and 1.1/1.5ma)
(!!!!) (Best Value Pair #1) 12AX7A RCA gray ribbed plates NOS 1967-1973 (best tone) (0.9/0.9ma and 0.9/1.1ma) (Fender)
(!!!!) (Best Value Single) 12AX7 Telefunken Germany <> bottom smooth plates branded GAP/R Computor tube like new 1964 (Gm=1700/1600 and 1.1/1.0ma)
(!!!) (Recommended Single) ECC83=12AX7 Mullard Webcor ribbed plates used/good 1962 (161 series) in white box (1.0/0.7ma and Gm=1600/1400)
(!!) (Best Value Pair) ECC83=12AX7 EI Yugo Telefunken NOS smooth plates clone rebranded Amperex and National (1.2/1.2ma and 1.2/1.3ma)
(!!!) (Good Value Single) 12AX7A RCA Magnavox ribbed plates used/good 1961 (Gm=1500/1900 and 0.8/1.3ma)
(!!!) (Best Single) 12AX7 Amperex Bugle Boy Holland "Long Plates" with "D" getter used/tests like new 1958 (Gm=1700/1800 and 1.6/1.5ma)
(!!!!!) (Best Overall Single 1957) 12AX7=ECC83 Mullard UK "long plates" NOS 1957 (1.3/1.3ma) 1% section balance (mC1 series)
(!!!) (Best Single) 12AX7A Sylvania NOS 1970's (Gm=2800/2900)
(!!!!) (Best RCA 1955) 12AX7 RCA black plates "D" getter NOS 1955 (Gm=1800/2000 and 1.2/1.5ma) (rare tube)
