(!!!!!) (Best Overall Single) JAN-5691 Sylvania black plates NOS 1977 (2.8/3.1mA) (Same Gm) (Best 6SL7GT sub) (same internals as 5691 red base)
(!!!!!) (Best Pair) 5U4GB CBS NOS 1950's double "D" getters (59-59/40 and 58-60/40)
(!!!!!) (Recommended Pair) 5U4GB HYTRON NOS 1960 "O" getter halos (56-58/40 and 57-58/40)
(!!!!!) (Recommended Pair) 5U4GB HYTRON NOS 1960 "O" getter halos (60-64/40 and 60-66/40)
(!!!!!) (Recommended Single) JAN-5691 Sylvania black plates NOS 1979 (2.2/2.4mA (Best 6SL7GT sub) (same internals as 5691 red base)
(!!!!) (Best Overall Pair) JAN-12AT7WC Sylvania black plates NOS 1979-1980 (9.8/10ma and 10.8/9.8ma)
(!!!!) (Best Overall Pair) JAN-6528A Raytheon NOS 1978 (132/138ma and 143/144ma)
(!!!!) (Best Pair) D3a=7721 Siemens Germany NOS 1978 (32.5/33ma) 1% matched
(!!!!) (Best Value Single) 12AX7 Hitachi Japan branded ITT NOS 1963 (1.0/1.7ma and Gm=1500/1950)
(!!!!) (Good Value Pair) JAN-12AT7WC Philips by Sylvania black plates NOS 1981-1982 (6.8/6.8ma and 7.0/7.2ma)
(!!!!) (Recommended Pair) JAN-12AT7WC Philips by Sylvania black plates NOS 1981-1982 (8.3/8.4ma and 8.4/7.8ma)
(!!!) (Best Value Pair) JAN-12AT7WC GE gray plates NOS 1970 (7.0/7.6ma and 7.0/8.2ma)
(!!!) (Best Value) 6681=12AX7 Hitachi Japan branded Amperex NOS 1970's (Gm=1400/1400 and 0.8/0.7ma)
(!!!) (READ REVIEW) GZ34 Mullard UK shield logo NOS 1962 (59/40 and 59/40)
(!!!) (Recommended Siemens Single) ECC81=12AT7 Siemens branded Mullard NOS circa 1970 (10.0/10.8ma)
(!!!) (Sylvania Pair #2) 5U4GB Sylvania NOS 1970's (60-62/40 and 60-62/40)
(!!) (Best Single) JAN-5693 GE JAN Black Can NOS 1978 (3.0ma)
(!!) (Best Single) JAN-CRC-5693 RCA red can NOS 1961 (3.3ma) (Peluso, Gibson)
(!!) (Single) JAN-CRC-5693 RCA red can NOS 1961 (2.6ma) (Peluso, Gibson)
(!!) 5693 RCA red can NOS 1949 (2.9ma)
