(slightly microphonic) 12BH7 GE Zenith NOS "U" getter 1953 (10.0/10.6ma)
(!!!!!) (Best Sylvania Pair) 12BH7A Sylvania gray pinched plates NOS 1970 era (9.8/10.4ma and 10/10.4ma) (same Gm)
(!!!!!) (Best Pair) 12BH7A GE gray oval plates "O" getter 1963-1965 same build (9.2/8.0ma and 8.4/8.8ma)
(!!!!) (Recommended Pair) 12BH7A GE NOS gray oval plates 1963-1965 (10/10.0ma and 9.2/10.4ma) (Quicksilver, Wells, Doshi, McIntosh)
(!!!!) (Recommended Single) 12BH7A Sylvania Hammond gray oval plates "D" getter halo used/like new 1959 (10.2/10.6ma)
(!!!!) (Recommended Single) 12BH7A Sylvania Hammond gray oval plates "D" getter halo used/like new 1959 (9/9ma)
(!!!!) 12BH7A Sylvania pinched plates NOS 1966 (10.5/15.4ma)
(!!!!) (Best Overall Single) 12BH7A Westinghouse gray ribbed plates NOS 1967 (10.6/10.8ma) (Same Gm) (similar to RCA)
(!!!) (Recommended Single) 12BH7A CBS Oval Black Plates "O" getter NOS 1960 (9.2/13ma)
(!!!) (Slightly microphonic Single) 12BH7A CBS Oval Black Plates "U" getter NOS 1960 era (8.4/9.0ma)
(!!!) 12BH7A RCA branded Zenith NOS 1970 era (10/13.2ma)
(Best RCA Pair) 12BH7A RCA gray ribbed plates NOS 1970 (12.6/13.6ma and 12.0/14.5ma) (Highest mA and Gm) (Wells, McIntosh)
(!!) (Recommended Single) 12BH7A Raytheon Black Plates "D" getter NOS 1955 (11.5ma/14.8ma)
(!!) 12BH7A National by Sylvania gray plates used/good 1970's (7.0/7.4ma)
(!!) 12BH7A Philco Sylvania gray oval plates "O" getter halo used/good 1962 (6.5/7.3ma)
(!!) 12BH7A RCA gray plates used/good 1960's (8.0/11.2ma)
(!!) 12BH7A RCA gray plates used/good 1970 era (8/9ma)
(!!) 12BH7A Sylvania rebranded Westinghouse NOS pinched plates 1960's 1% section balance (7/7ma)
(!!) 12BH7A Westinghouse black plates "U" getter used/good 1950's (6.2/7.2ma)
(!) 12BH7A GE gray oval plates "O" getter halo used/good 1964 (7.2ma/8.5ma)
