(!!!!) (Best Value Pair 1965 era) 12AX7=ECC83 Philips Miniwatt Holland like new 1964-1965 era (1.3/1.2ma and 1.1/1.2ma)
(!!!!) (Best Value Pair) 12AU7 Philips Holland NOS 1971-1972 dimpled disc halo (10.2/10.6ma and 11.2/11.6ma)
(!!!!) (Best Value Pair) 6B4G Raytheon NOS 1940's separate plates, 1 branded Philco (90ma and 91.5ma)
(!!!!) (Best Value Single) 5U4GB RCA Super Airline NOS 1960 era (58/40 and 60/40)
(!!!!) (Best Value Single) 6550 Tungsol branded Sylvania smooth gray plate used/tests like new 1960 era (138ma)
(!!!!) (Best Value Single) 6922=E88CC Penta Labs Hungary used/like new 1980 era (13.8/15.8ma)
(!!!!) (Best Value used) ECC83=12AX7 Fisher Mullard ribbed plates used/good 1964 (.8/1.2mA Gm=1400/1600)
(!!!!) (Best Value used) ECC83=12AX7 Fisher Mullard ribbed plates used/good 1964 copper grid posts (.7/.8mA Gm=1400/1500)
(!!!!) (Good Value 1962) M8137=12AX7S Philips SQ France ribbed plates NOS 1962 (0.8/0.9ma and Gm=1350/1350) (Special Quality 12AX7)
(!!!!) (Good Value 1962) M8137=12AX7S Philips SQ France ribbed plates NOS 1962 (1.1/1.1ma and Gm=1550/1450) (Special Quality 12AX7)
(!!!!) (Holland Single) 12AU7 Philips Miniwatt Holland like new 1961 large "O" getter halo (9.6/11ma)
(!!!!) (microphonic single) 6922=E88CC Siemens Halske Germany gray shield NOS 1965 (A0 Series=1st series) (15.2/15.8ma)
(!!!!) (Pair) 6B4G Raytheon NOS 1940's - 1 tube branded Tungsol - same build - separate plates (100ma and 109ma)
(!!!!) (Pair) 6B4G Raytheon NOS 1940's - 1 tube branded Tungsol - same build - separate plates (82ma and 83ma)
(!!!!) (Pair) 6B4G Raytheon NOS 1940's - 1 tube branded Tungsol - same build - separate plates (86ma and 92ma)
(!!!!) (Recommended Pair) 12AX7=ECC83 Philips and Pope Holland NOS 1965-1967 (2.1/1.8ma and 1.6/2.1ma) (Highest mA and Gm)
(!!!!) (Recommended Pair) 6BQ5 RCA NOS 1960's (50.5ma and 48.2ma)
(!!!!) (Recommended Pair) EL34 Mullard branded Siemens and RCA XF2 single "O" getter halos NOS 1969-1972 (78ma and 81.5ma)
(!!!!) (Single 1965) EL34 Philips Miniwatt by Mullard XF2 double round getter halo "O-O" NOS 1965 (76ma)
(!!!!) (Single) 6922=E88CC Penta Labs Hungary used/good 1980 era (10/15ma)