(!!!!) (BEST OVERALL SINGLE) 12AU7A GE NOS 1958 copper grid posts (11.8/11.4ma) 1-3% section balance
(!!!!) (BEST SINGLE 1985) 12AU7A GE NOS 1985 copper grid posts (9.2/9.4ma) 1-2% section balance
(!!!!) (SINGLE) 12AU7A GE NOS 1976 copper grid posts (9.4/8.8ma)
(!!!!) (SINGLE) 12AU7A GE NOS 1972 copper grid posts (10.6/9.8ma) (warm and smooth)
(!!!!!) (Best Overall Pair 1965) 12AU7=ECC82 Mullard UK NOS branded Philips 1965 (10/10.3ma and 9.8/10.0ma) (same Gm) (Rogue, Hovland, Audio Note)
(!!!) (Single) 12AU7A RCA clear top NOS 1968 (8/11ma)
(!!!) (Recommended Single) 12AU7A RCA clear top NOS 1960 era (9.6/9.8ma) (Same Gm)
(!!!!) (Recommended Single) CV4003=12AU7=6189 Mullard UK NOS 1978 rebranded "6189 RTC" 1981 (9.6/10.8mA)