(!!!) (Recommended Single) 5691 RCA Red Base black plates used/good 1959 (2.3/2.0ma)
(!!!) (Recommended Single) 6SL7GT Ken Rad NOS 1945 era (2.1/2.3ma)
(!!!) (Recommended Single) 6SL7GT RCA NOS 1962 (2.5/2.7ma)
(!!!) (Slightly Microphonic Single) CV1985=6SL7GTY Brimar UK tests like new 1950's (2.2/2.2ma)
(!!!) 6SL7GT Sylvania round gray plates like new 1951 (3.7/3.6ma) (Highest mA and Gm)
(!!!) 6SL7WGT Sylvania branded Raytheon 5691 brown base round black plates "D" getter halo used/good 1950's (1.6/1.8ma)
(!!!) 6SL7WGT Sylvania brown base round black plates like new 1955 no printing (2.6/2.8ma)
(!!) (Best Pair) JAN-CHS-6SL7WGT Sylvania brown base "square getter halo" like new faded printing (2.4/2.6ma and 2.4/2.4ma) 1-3% matched
(!!) (Best Value) VT-229=JAN-CHS-6SL7GT Sylvania NOS white printing 1944-1945, hairline crack in base, mis-matched sections in white box (2.6/3.4ma)
(!!) (recommended Single) 6SU7GTY=6188 Tungsol 1950's rebranded "5691 NATIONAL" in 1980's black ribbed plates "D" getter halo triple mica (2.3/2.5ma)
(!!) (single) 6SL7GT RCA NOS black plates gray coated glass 1959 (2.0/1.7ma)
(!!) (slightly microphonic pair) JAN-6SL7GT=VT-229 RCA NOS and like new 1940's (2.5/2.4ma and 2.4/2.6ma) 1-3% matched
(!!) (slightly microphonic) 6SL7GT RCA NOS 1950 (2.2/2.3ma) 1-2% section balance
(!!) (slightly microphonic) 6SL7GT RCA NOS black plates gray coated glass 1952 (2.8/2.8ma) 1% section balance
(!!) 6SL7GT Sylvania NOS 1960's (2.6/2.2ma) (Eddie Current)
(!!) 6SL7GT Sylvania NOS branded Westinghouse tall bottle 1955 (2.8/2.7ma)
(!!) 6SL7GT Sylvania NOS branded Zenith 1950's tall bottle (3.0/2.9ma)
(!!) 6SL7GT Sylvania NOS tall bottle 1955 (2.0/2.2ma)
(!) (SINGLE) 6SL7GT RCA round black plates NOS 1970 (2.0/2.1ma)
(!) (slightly microphonic) 6SL7GT=VT-229 RCA round black plates like new 1942-1945 era (2.4/2.6ma)
