(!!!!!) (Best Pair) JAN-5691 Philips by Sylvania black plates NOS 1985 (2.3/2.6mA and 2.3/2.4mA) (Best 6SL7GT sub) (same internals as 5691 red base)
(!!!!!) (Best Pair) JAN-5691 Sylvania black plates NOS 1977 (2.1/2.2mA and 2.1/2.3mA) (Best 6SL7GT sub) (same internals as 5691 red base)
(!!!!!) (Best Pair) JAN-5691 Sylvania black plates NOS 1979 (2.0/2.1mA and 2.1/2.1mA) (Best 6SL7GT sub) (same internals as 5691 red base)
(!!!!!) (Best Quad) JAN-5691 Sylvania black plates NOS 1979 1-3% matched (Cary, Rogue) (Best 6SL7GT sub) (same internals as 5691 red base)
(!!!!!) (Recommended Pair) JAN-CTL6SL7WGT Tungsol NOS brown base gray ribbed plates 1961-1965 (2.1/2.2ma and 2.1/2.3ma) (low noise - very smooth sound) (phono grade)
(!!!!) (Best Single 1960's) 5691 RCA Red Base branded GE Black Plates NOS 1960's rebranded in 1970's (2.4/2.6ma)
(!!!!) (Best Pair) VT-229=JAN-CHS-6SL7GT Sylvania round black plates NOS 1944 (2.1/2.2ma and 2.0/2.1ma) close triode balance
(!!!) (Good Value Pair) 6SL7GT Sylvania Zenith tall bottle black plates used/good 1960 era (2.0/2.1ma and 2.2/2.4ma)
(!!!) (slightly microphonic - low noise) 6SL7GT Brimar NOS black base gray plates 1950's (2.3/2.7ma)
(!!!) (Slightly Microphonic Single) CV1985=6SL7GTY Brimar UK tests like new 1950's (2.2/2.2ma)
(!!!) 6SL7WGT Sylvania branded Raytheon 5691 brown base round black plates "D" getter halo used/good 1950's (1.6/1.8ma)
(!!!) (Best Value) VT-229=6SL7GT Sylvania round black plates used/like new 1940's (2.5/2.7ma) (Gm like new)
(!!) (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)
(!!) (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 (1.8/2.0ma) (Eddie Current)
(!!) 6SL7GT Zenith Sylvania tall bottle NOS 1960 (2.4/2.2ma) (Eddie Current)
(!!!) (Recommended Pair) 5691 RCA red base gray plates 1968-1974 (2.2/2.4ma and 2.1/2.3ma)
(!!) (Best Pair) 7F7 Sylvania round gray plates NOS 1950-1952 (2.3/2.7ma and 2.3/2.6ma) 1-2% matched