(!!!!) (Recommended Pair) 403B Western Electric NOS "D" getter 1969 (5.6/5.6ma) 1% matched
(!!!!) (Recommended Quad) 403B=6AK5 Western Electric NOS "D" getter 1969 matched set of 4 (6.9, 6.9, 7.1, 7.2ma)
(!!!!) (Recommended Quad) 403B=6AK5 Western Electric NOS "D" getter 1969 matched set of 4 (4.8, 4.9, 5.1, 5.2ma)
(!!!!) (Recommended Quad) 403B=6AK5 Western Electric NOS "D" getter 1969 matched set of 4 (6.3, 6.3, 6.4, 6.5ma)
(!!!!) (1 Pair) 5654=6AK5W GE NOS 1983 (7.3ma and 7.9ma) (same Gm)
(!!!!) (Best Overall Pair) JHY-6AK5 Hytron black plate NOS 1952 (8.1ma and 8.1ma) 1-2% matched
(!!!!) (Recommended Pair) JHY-6AK5 Hytron black plate NOS 1952 (7.3ma and 7.6ma)
(!!!!) (2nd Best Pair) JHY-6AK5 Hytron black plate NOS 1952 (9.8ma and 9.4ma) 1-5% matched
(!!!) (Recommended Pair) JHY-6AK5 Hytron black plate NOS 1952 (8.0ma and 8.2ma)
(!!!) (Recommended Pair) JHY-6AK5 Hytron black plate NOS 1952 (5.8ma and 5.8ma)