(!!!!!) (Best Pair) 6189W Sylvania NOS 1981 (9/10.2ma and 10/9ma) 1-3% matched (same Gm)
(!!!!) (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 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 Overall Pair) JAN-6189W Sylvania NOS 1977-1978 (8.7/9.1ma and 8.6/8.8ma) 1-2% matched
(!!!!) (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 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) JAN-6189=12AU7WA Sylvania NOS 1972-1973 (9.3/10.4ma and 9.6/10.6ma) 1-3% matched
(!!!!) (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 (10.4/11.4ma and 10.0/11.0ma)
(!!!!) (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
(!!!!) (Recommended Pair) CV4003=12AU7=6189 Mullard UK NOS 1978 rebranded "6189 RTC" 1981 (9.6/8.8ma and 9.4/9.0ma) 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)
(!!!!) (Recommended Pair) JAN-6189W=12AU7WA Sylvania NOS 1973-1974 (9.2/9.6ma and 9.8/8.6ma)
(!!!) (BEST PAIR) JG-6189=12AU7WA GE double mica NOS 1963-1964 (10.2/12ma and 10.2/11ma)
(!!!) (Good Value Single) JAN-6189=12AU7WA Sylvania NOS 1960 era in white box (8.6/10ma)
(!!!) (SINGLE) 12AU7 RCA tall black plates "D" getter used/good 1950's (9.8/8.2ma)
(!!!) 12AU7 RCA tall gray plates "D" getter used/good 1953 (9.2/9.8ma)
(!!!) 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 Single) 12AU7WA=6189 Sylvania NOS 1960's (10/10ma)
