(!!!!!) (Recommended Pair) 12BH7A GE gray oval plates "O" getter 1965-1966 same build (10.0/10.2ma and 12/11ma)
(!!!!) (BEST OVERALL PAIR) ECF80=6BL8 Mullard rebranded Philips NOS 1966 1-5% matched
(!!!!) (Best Overall Single) 12BH7A Westinghouse gray ribbed plates NOS 1967 (10.6/10.8ma) (Same Gm) (similar to RCA)
(!!!!) (BEST PAIR) 7027A RCA NOS 1963 and 1972 (73ma and 73.6ma)
(!!!!) (Good Value Pair) 12BH7A GE NOS gray oval plates "o" getter halo 1961-1965 (7.2/6.6ma and 8.4/6.8ma)
(!!!!) (Good Value Single) 12BH7A RCA gray plates used/like new 1960's (8.5/9ma)
(!!!!) (Recommended Single) 12BH7A RCA rebranded Westinghouse black plates "U" getter NOS 1955 (8.4/12.8ma)
(!!!) (Best Mullard Single) ECF80=6BL8 IEC Mullard UK NOS 1966 (16ma/12ma) (Highest mA and Gm)
(!!!) (Best Value Pair) 6BL8 Motorola Golden JAPAN by Toshiba "Premium Rated" NOS 1974 (1 pair)
(!!!) (Good Value) 12AX7A RCA gray ribbed plates "O" getter halo NOS 1973 (1.0/0.9mA and Gm=1400/1550)
(!!!) (Good Value) 12AX7A RCA gray ribbed plates "O" getter halo NOS 1974 (0.8/1.0mA and Gm=1350/1550) (Fender, McIntosh)
(!!!) (Recommended Pair) 12AZ7A GE gray plates NOS 1969-1970 (8.2/8.0ma and 8.7/8.8ma) (McIntosh MC275)
(!!!) (Recommended Pair) 12AZ7A RCA black plates NOS 1970's (8.6/9.6ma and 7.6/9.2ma) (McIntosh MC275)
(!!!) (Recommended Pair) 12BH7A Sylvania NOS 1960's - 1970's (9.2/8.5ma and 8.6/9.0ma) (same Gm)
(!!!) (Recommended Pair) 7591A GE coin-base NOS original boxes 1981 (62ma and 62.5ma)
(!!!) (Recommended Pair) 7591A GE coin-base NOS original boxes 1981 (79ma and 83ma)
(!!!) (Recommended Single) 12BH7A Westinghouse black ribbed plates "U" getter halo 1961 (8.5/10ma)
(!!!) (Recommended Single) EF94=6AU6 Mullard England NOS 1963 (6.5ma)
(!!!) (Recommended Single) EF94=6AU6 Tungsol used/tests like new 1957 (10ma)