(!!) (Recommended Pair) 6S4A Westinghouse black plate NOS -1963 era (20ma and 21.2ma)
$ 19.99
1 pair) 6S4A Westinghouse black plate NOS -1963 era
1 tube) 21.2ma and Gm=4200 (1963)
1 tube) 20.0ma and Gm=4200 (1963 era)
Tested on Amplitrex
Vplate=250V
Vgrid=-8V
Good Ma range 20-25ma
Good Gm range 4000-4500
(the 6S4A features high plate current at relatively low plate voltages and is capable
of withstanding high pulse voltages)(Vfil=6.3V @ 600ma)
MAX Ratings: Vplate=550V, Iplate=30ma, Pout=8.5 watts
Typical Operation: Vplate=250V, Vgrid=-8V, Iplate=24ma, Mu=16.5, Gm=4500, Rplate=3700 ohms)
- Woo Audio GES Electrostatic headphone amp
See more: vacuum tube