(!!!!) (Recommended Pair) JAN-6189W=12AU7WA Sylvania NOS 1973-1974 (9.2/9.6ma and 9.8/8.6ma)
(!!!!) (Recommended Pair) JAN-6189W Sylvania NOS 1974-1976 (9.2/10.2ma and 9.3/9.4ma) (Same Gm)
(!!!) 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)
(!!!) (BEST PAIR) JG-6189=12AU7WA GE double mica NOS 1963-1964 (10.2/12ma and 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)
(!!) (Best Single) 12AU7WA=6189 Sylvania NOS 1960's (10/10ma)
(!!!!) (Recommended Pair) CV4003=12AU7=6189 Mullard UK NOS 1978 rebranded "6189 RTC" 1981 (9.0/10.4ma and 9.4/10.0ma) 1-3% matched
(!!!!) (Best Overall Pair) CV4003=12AU7=6189 Mullard UK NOS 1978 rebranded "6189 RTC" 1981 (9.6/9.6ma and 9.4/9.8ma) 1% matched (can make a quad with another pair)
(!!!!) (Best CV4003 Quad) CV4003=12AU7=6189 Mullard UK NOS 1978 rebranded "6189 RTC" 1981 (8.4/9.0, 8.4/9.0, 8.4/8.8, 8.4/8.8mA)
(!!!!) (Best Overall Quad) CV4003=12AU7=6189 Mullard UK NOS 1978 rebranded "6189 RTC" 1981 (8.8/8.8, 8.8/8.8, 8.6/8.8, 8.6/9.0mA)
(!!!!) (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)
(!!!!) (Recommended Pair) CV4003=12AU7=6189 Mullard UK NOS 1978 rebranded "6189 RTC" 1981 (9.6/9.4ma and 9.8/9.6ma) 1-3% matched (same Gm)
(!!!) (Good Value Single) JAN-6189=12AU7WA Sylvania NOS 1960 era in white box (8.6/10ma)
