(!!!!) (Best Value Single) 12AU7=ECC82 Mullard UK ribbed plates like new 1965 (10/12.8ma) (smooth rich sound)
(!!!) 12AU7A GE "U" getter low hours/tests like new 1957 (10.0/8.8ma)
(!!!) (BEST PRICE) 12AU7A GE used/good 1969 - 1980 (4 for $29.99)
(!!!) (Best Pair) 5963=12AU7 Sylvania NOS 1960's (11.4/11.2ma and 11.2/11.4ma) (same Gm) 1% matched
(!!!) (Best Value Single) ECC82=12AU7 Philips Holland branded SONOTONE NOS 1960 (10.0/9.2ma)
(!!!!) (Recommended Pair) CV4003=12AU7=6189 Mullard UK NOS 1978 rebranded "6189 RTC" 1981 (10.4/11.4ma and 10.6/11.8ma)
(!!!!) (Best Pair) 12AU7=ECC82 Mullard Philips UK ribbed plates NOS 1974 same date codes 1-2% matched (9.8/9.6ma and 9.6/10.0ma) (Rogue, Hovland, Audio Note)
(!!!!) (2nd Best Pair - warm and smooth) 12AU7A GE NOS 1974-1981 (8.2/8.8ma and 8.3/8.8ma) (Rogue)
(!!!!) (Recommended Single) 12AU7=ECC82 Mullard UK ribbed plates NOS 1972 (12.2/13.6ma) (same Gm) (smooth rich sound)
(!!!!!) (Best Pair 1974) 12AU7 Mullard UK NOS 1974 (10.5/10.7ma and 10.4/11.5ma) (Rogue, Hovland, Audio Note)
(!!!) (Best Single) 6189=12AU7WA=E82CC Sylvania NOS 1960's in white box (10/10.2ma) (Same Gm) 1-2% section balance
(!!!!) (Best Single 1959) ECC82=12AU7 Miniwatt Holland "D" getter 1959 (ct3-delta9I) (11.2/11.4ma)
(!!!!) (Single 1955) 12AU7 Brimar UK NOS gray ribbed plates "D" getter halo 1955 (8.2/10.4ma)
(!!!!) (Best Overall Single) CV4003=12AU7=6189 Mullard UK NOS 1978 rebranded "6189 RTC" 1981 (10.8/11.2ma) 1-3% section balance
(!!!!) (Best Overall Single) CV4003=12AU7=6189 Mullard UK NOS 1978 rebranded "6189 RTC" 1981 (13/12.8ma) (Highest mA and Gm)
(!!!!) (Best Pair) 5963=12AU7 Sylvania NOS 1960's (10.6/11.4ma and 10.6/11.4ma) 1% 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
(!!!) (Best Overall Pair) 5963=12AU7 Sylvania NOS 1960's (10/10.6ma and 10/10.6ma) 1% matched
(!!) (BEST GE Pair) 5963 GE branded RCA NOS ribbed plates 1978 (12.2/13.0ma and 12.4/13.6ma)
(!!) (BEST GE Pair) 5963 GE branded RCA NOS ribbed plates 1978 (13.0/11.4ma and 12.6/11.4ma)