(!!!!!) (Best Overall Pair) 311B Western Electric NOS 1972-1974 (32ma and 33.4ma)
$ 169.99
1 pair) 311B Western Electric NOS 1972-1974 original boxes
1 tube) 32.0ma and Gm=3060 (1972)
1 tube) 33.4ma and Gm=3100 (1974)
Tested on Amplitrex
Vplate=180V
Vscreen=135V
Vgrid=-15V
Good Ma = 30ma
Good Gm = 2900
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