(!!!!!) (Best Overall Pair) 6SN7GT Tungsol parallel gray plates large O mica NOS 1952-1953, 1 tube has crack in base (8.8/8.2ma and 8.8/8.2ma) 1-2% matched (Cary, Rogue)
(!!!!!) (Best Overall Pair) ECC33=6SN7GT Mullard UK black plates NOS pan shape getter halo 1950-1955 era (9.4/8.6ma and 9.4/8.4ma) 1-2% matched (best sounding ECC33 of all-time)
(!!!!!) (Best Pair) 6SN7GT Tungsol parallel gray plates 1954 (8.7/7.5ma and 8.0/7.5ma) (very close Gm) (Cary, Rogue)
(!!!!!) (Best Value Pair) 6SN7GTB GE NOS 1955-1964 same build (6.1/6.5ma and 6.0/6.3ma)
(!!!!!) (Best Value Pair) 6SN7GTB GE NOS 1964-1965 same build (6.4/7.0ma and 6.6/7.6ma)
(!!!!!) (Best Value Pair) 6SN7GTB RCA NOS and like new 1965 (8.2/10.2ma and 8.2/9.2ma) (same Gm) (warm and smooth)
(!!!!!) (Best Value Pair) 6SN7GTB Sylvania "chrome top" NOS and like new 1956 (8.1/8.6ma and 7.8/8.6ma) (strong Gm)
(!!!!!) (Good Value Pair) 6SN7GTA Ken Rad black plates NOS "U" getter halo 1951 slightly tilted glass (10.0/10.2ma and 9.0/9.8ma)
(!!!!!) (Recommended Pair) 6SN7GT Tungsol parallel gray plates large "O" mica ears NOS 1953 (6.4/6.6ma and 6.4/6.8ma) (rare version) (Cary, Rogue)
(!!!!!) (Recommended Pair) ECC33=6SN7GT Mullard UK black plates NOS pan shape getter halo 1950-1955 era (10.2/8.6ma and 9.5/8.6ma) (best sounding ECC33 of all-time)
(!!!!!) (Recommended Pair) ECC33=6SN7GT Mullard UK black plates NOS pan shape getter halo 1950-1955 era (8.6/9.6ma and 8/10ma) (best sounding ECC33 of all-time)
(!!!!!) (Recommended Pair) ECC33=6SN7GT Mullard UK black plates NOS pan shape getter halo 1950-1955 era (9.6/9.8ma and 9.6/10.6ma) (Highest mA and Gm) (best sounding ECC33 of all-time)
(!!!!) (Best Pair) 6SN7GTA GE "U" getter halo - side getter - copper grid posts NOS 1951-1952 (10.4/12.2ma and 10.6/10.8ma)
(!!!!) (Best Single) 5692 CBS Hytron Brown base NOS 1957 (9.4/9.0ma) (same Gm)
(!!!!) (Best Single) 5692 RCA RED BASE black plates like new 1950 (10.0/9.2ma)
(!!!!) (Best Single) 6SN7GTA GE NOS "U" getter halo - side getter - copper grid posts 1952 (8.8/7.8ma)
(!!!!) (Best Single) 6SN7GTA GE NOS "U" getter halo - side getter - copper grid posts 1952 (9.3/11ma)
(!!!!) (Best Single) 6SN7GTA Sylvania Philco "Chrome Top" short bottle NOS 1954 (7.8/8.0ma) 1-3% section balance
(!!!!) (Best Single) 6SN7GTB RCA NOS 1958 side getter (9.6/9.8ma)
(!!!!) (Best Single) 6SN7GTB RCA NOS 1960 (10/11ma) (Highest Gm)
