(!!!!) (Recommended Pair) EL34 Mullard branded Siemens and RCA XF2 single "O" getter halos NOS 1969-1972 (78ma and 81.5ma)
(!!!!) (Single) 6922=E88CC Penta Labs Hungary used/good 1980 era (10/15ma)
(!!!) (Best Single 1963) JG-5751 GE double mica gray plates NOS 1963 (2.7/2.7ma) (1-2% section balance)
(!!!) (Best Single) 6SN7GT Tungsol parallel black plates chrome top NOS 1952-1953 (11.4/11.2ma)
(!!!) (Best Single) 6SN7GT Tungsol parallel gray plates NOS 1953 (10.4/9.6ma)
(!!!) (Best Single) 6SN7GT Tungsol parallel gray plates NOS 1953 burgundy base large "O" mica (9/10ma)
(!!!) (Best Single) 6SN7GT Tungsol parallel gray plates NOS 1953 large "O" mica (10.4/9.2ma)
(!!!) (BEST SINGLE) E81L=6686 Siemens made By Valvo, Hamburg, Germany NOS 1963 (22ma)
(!!!) (Best Value Pair) 5751 GE double mica gray plates NOS 1979-1981 (2.4/2.5ma and 2.3/2.6ma)
(!!!) (Best Value Single) 12AU7=ECC82 Telefunken smooth plates like new 1963 (10/8.4ma)
(!!!) (Best Value Single) 12AX7=ECC83 SIEMENS HALSKE GERMANY like new 1966 (1.0/1.1ma)
(!!!) (Best Value Single) 6SN7GT Tungsol parallel gray plates NOS 1953 large "O" mica (7.0/7.2ma)
(!!!) (Good Value Single) 12AU7 Philips Australia NOS 1970 era (9.6/8.8ma) (same internals as Holland made)
(!!!) (Good Value Single) 5U4G=VT-244 Sylvania used/good 1940's (51/40 and 52/40)
(!!!) (Good Value Single) 5U4G=VT-244 Sylvania used/good 1940's (52/40 and 56/40)
(!!!) (Good Value Single) 6SN7GTB Tungsol tall bottle used/good 1960 era (7.5/7.5ma) 1% section balance
(!!!) (PAIR) 5881 Tungsol tests like new 1957 and 1963 with broken center guide pins - see photo (72.5ma and 68.2ma)
(!!!) (Recommended Pair 1963) JG-5751 GE double mica gray plates NOS 1963 (2.0/1.9ma and 1.9/1.8ma) (same Gm)
(!!!) (Recommended Pair) 12AU7A GE NOS 1965-1975 (8.8/8.8ma and 9.2/8.8ma) (Same Gm) (smooth and warm)
(!!!) (Recommended Pair) 12BZ7 RCA NOS 1964 and 1968 (1.8/1.8ma and 1.8/1.9ma)
