(!!!!) (Best Pair) 6189W Sylvania NOS 1976-1979 (9.5/9.6ma and 9.2/10.2ma) 1-3% matched
(!!!!) (Recommended Pair) JAN-6189W=12AU7WA Sylvania NOS 1972-1973 (9.6/10.6ma and 9.3/10.4ma) 1-3% matched
(!!!!) (Recommended Pair) CV4003=12AU7=6189 Mullard UK NOS 1978 rebranded "6189 RTC" 1981 (10.4/11ma and 10.4/10.8ma) 1-2% matched
(!!!) 6189=12AU7WA RCA black plates NOS 1971 (9.0/9.6ma)
(!!!) 6189=12AU7WA Sylvania Heintz and Kaufman NOS 1976 (9.0/9.6ma)
(!!!) (Best RCA Single) USAF-6189=12AU7WA RCA black plates "D" getter NOS 1961 (9.8/10.2ma)
(!!!) (Recommended Pair) JAN-6189=12AU7WA Sylvania NOS 1973-1974 (8.4/9.8ma and 9.2/9.6ma)
(!!!) (Recommended Pair) JAN-6189W Sylvania NOS 1977-1978 (8.7/9.1ma and 8.6/8.8ma) 1-2% matched
(!!!) JHS-6189=12AU7WA Sylvania NOS 1966 in white box (8.5/10.2ma)
(!!!) JHS-6189=12AU7WA Sylvania NOS 1966 in white box (9.6/11.4ma)
(!!) (Best Value Pair) 6189W Philips ECG NOS by Sylvania 1983-1987 (8/10ma and 8.6/10ma)
(!) 6189=12AU7A GE NOS 1975 (9.6/10ma) 1-2% section balance
(!!!) 12AU7 RCA tall gray plates "D" getter used/good 1953 (9.2/9.8ma)
6189W GE JAN NOS 1973 mica flake inside tube (9.0/9.2ma) 1-2% section balance
6189W GE JAN NOS 1981 (8.4/9.0ma)
6189W GE JAN NOS 1985-1986 (9/11.2ma)
JG-6189=12AU7WA GE double mica NOS 1963-1964 (10.2/12ma)
JG-6189=12AU7WA GE NOS 1964 (10.2/11ma)
JG-6189=12AU7WA GE triple mica NOS 1963 (8.6/10.4ma)
(!!) 12AU7WA=6189 Sylvania NOS 1960's (8.8/9.0ma)
