(!!!!) (Best Overall Single) CV4003=12AU7=6189 Mullard UK NOS 1978 rebranded "6189 RTC" 1981 (13/12.8ma) (Highest mA and Gm)
(!!!!) (Best Overall Single) ECC802S=12AU7 Telefunken Germany <> bottom NOS 1970 (10.2/11.2ma)
(!!!!) (Best Overall Single) GB-5963=12AU7 Sylvania Gold Brand Gold Pins NOS 1960's (11.2/13.6ma)
(!!!!) (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 1966) 12AU7A GE NOS 1966 (9.8/10.6ma and 11.2/9.8ma) (Close Gm) (Warm and smooth)
(!!!!) (Best Pair) 12AU7A RCA clear top NOS 1960's (10/8.5ma and 9.4/8.8ma) (same Gm)
(!!!!) (Best Pair) CV4003=12AU7=6189 Mullard UK NOS 1978 rebranded "6189 RTC" 1981 (10.2/11.2ma and 10.4/11.2ma) 1-2% matched
(!!!!) (Best Pair) ECC82=12AU7 Philips Holland NOS 1972 (12/12ma and 11.2/11.8ma) (Highest mA and Gm)
(!!!!) (Best Pair) JAN-6189=12AU7WA Sylvania NOS 1972-1973 (9.3/10.4ma and 9.6/10.6ma) 1-3% matched
(!!!!) (Best Pair) JTL-5814A Tungsol ribbed plates 1959-1960 (10.6/10.0ma and 10.0/10.4ma)
(!!!!) (Best Quad) CV4003=12AU7=6189 Mullard UK NOS 1978 rebranded "6189 RTC" 1981 (8.8/9.5, 8.8/9.4, 9.0/9.3, 9.0/9.4mA) (Highest Gm 1-2% matched)
(!!!!) (Best RCA Pair) 12AU7A RCA long gray ribbed plates "D" getter NOS 1958 (9.8/8.4ma and 8.4/9.4ma)
(!!!!) (Best Single #3) ECC82=12AU7 Telefunken Diamond Bottom smooth plates NOS 1964 copper grid posts (10.6ma/10.2ma) 1-3% section balance
(!!!!) (Best Single 1956) 12AU7=ECC82 Amperex Holland "long-plates" large "D" getter with crossbar like new 1956 (9.2/8.2ma) (rare)
(!!!!) (Best Single 1959) ECC82=12AU7 Miniwatt Holland "D" getter 1959 (ct3-delta9I) (11.2/11.4ma)
(!!!!) (Best Single 1965) ECC82=12AU7 Miniwatt Holland like new 1965 (9.4/9.4ma) 1% section balance
(!!!!) (Best Single) 12AU7=ECC82 Mullard UK ribbed plates NOS 1972 (12.2/13.6ma) (same Gm) (smooth rich sound)
(!!!!) (BEST SINGLE) 12AU7A GE NOS 1963 copper grid posts (11.4/11.6ma) 1-2% section balance
(!!!!) (Best Single) ECC82=12AU7 Telefunken Diamond Bottom ribbed plates like new 1960 (10.6/10.2ma) (same Gm)
(!!!!) (Best Value Single) 12AU7=ECC82 Mullard UK ribbed plates like new 1965 (10/12.8ma) (smooth rich sound)
