(!!!!) (Best Single 1957) JG-5751WA GE NOS black plates triple mica U getter halo 1957 (2.3/2.7ma) (High mA and Gm)
(!!!!) (Best Single 1958) 5751 Sylvania black plates triple mica D getter halo 1958 like new (2.5/2.3ma)
(!!!!) (Best Single 1959) ECC82=12AU7 Miniwatt Holland "D" getter 1959 (ct3-delta9I) (11.2/11.4ma)
(!!!!) (Best Single 1960's) 5691 RCA Red Base branded GE Black Plates NOS 1960's rebranded in 1970's (2.4/2.6ma)
(!!!!) (Best Single 1961) 12AX7=ECC83 Mullard UK ribbed plates NOS 1961 (161 Series) (1.1/1.1ma and Gm=1600/1700)
(!!!!) (Best Single 1961) 12AX7=ECC83 Philips Miniwatt Holland 1961 large "O" getter halo NOS (1.8/1.3ma and Gm=2100/1700)
(!!!!) (Best Single 1965) ECC82=12AU7 Miniwatt Holland like new 1965 (9.4/9.4ma) 1% section balance
(!!!!) (Best Single) 12AT7=ECC81 Mullard UK NOS 1972 (10.4/10.2ma)
(!!!!) (Best Single) 12AU7=ECC82 Mullard UK ribbed plates NOS 1972 (12.2/13.6ma) (same Gm) (smooth rich sound)
(!!!!) (BEST SINGLE) 12AU7A GE NOS 1963 copper grid posts (11.4/11.6ma) 1-2% section balance
(!!!!) (Best Single) 12AX7 GE NOS tall ribbed plates 1964 (1.3/1.2ma Gm=1700/1700) 1-2% section balance
(!!!!) (Best Single) 12AX7WA Sylvania NOS 1970's (Gm=3000/3100 and 2.5/2.5ma)
(!!!!) (Best Single) 12BH7 GE NOS gray oval plates "U" getter 1953 (13.8/14.2) (Quicksilver, Wells, Doshi, McIntosh)
(!!!!) (Best Single) 12BH7 Sylvania Silvertone black oval plates "D" getter NOS 1954 (14.4/12.2ma)
(!!!!) (Best Single) 12BH7A GE ribbed plates NOS 1980 (10.0/10.2ma) 1-3% section balance
(!!!!) (Best Single) 12BH7A RCA gray plates NOS 1970 (10.6/10.2ma)
(!!!!) (Best Single) 12BH7A RCA NOS 1960's (11.6/12.6ma)
(!!!!) (Best Single) 12BH7A Sylvania rebranded GE black oval plates "U" getter NOS 1956 era (11.2/14ma)
(!!!!) (Best Single) 12BH7A Tungsol black plates "O" getter halo 1960 era (11.0/11.6ma)
(!!!!) (Best Single) 12SN7GTA Sylvania branded GE NOS 1960's (11.0/11.4ma) (same Gm)
