(!!!!) (Recommended Pair) 448A Western Electric tipped top used/test like new 1965-1966 (37.8ma and 39.0ma) (close Gm matching)
(!!!!) (Recommended Pair) 6BQ7A RCA black plates NOS 1964-1968 (9.2/11.2ma and 10.2/11ma)
(!!!!) (Recommended Pair) 6BQ7A RCA black plates NOS 1967 same date codes (11.8/12ma and 11/12.2ma)
(!!!!) (Recommended Pair) 6JB6A RCA NOS 1970 era (62ma and 66ma) (DRAKE)
(!!!!) (Recommended Pair) 6LQ6=6JE6C Sylvania NOS 1970 era (76ma and 77ma)
(!!!!) (Recommended Pair) 6N7 Sylvania metal can NOS 1945 (3.4/3.4ma and 3.1/3.0ma) 1-5% matched
(!!!!) (Recommended Pair) 83 GE NOS 1960's (62-65/40 and 62-63/40)
(!!!!) (Recommended Pair) JAN-CRC-30 RCA NOS 1940's same build (2.9ma and 3.0ma)
(!!!!) (Recommended Philips Pair) 5814A Philips JAN NOS 1985 (9.5/10.5ma and 10/11.2ma) (same Gm)
(!!!!) (Recommended Quad) 6HA5=6HM5=EC900 Amperex Holland "Globe Logo" NOS in white boxes 1971 (9.8/9.8/10.0/10.2ma)
(!!!!) (Recommended Single) 12AU7A RCA clear top NOS 1969 (10.6/12.0ma)
(!!!!) (Single) 6BK7B GE gray plates NOS "U" getter 1963 (6.2/5.4ma)
(!!!!) (Single) 6BK7B RCA NOS "U" getter 1950's (7.5/8.5ma)
(!!!!) (Single) 6BK7B Tungsol branded RCA "U" getter 1957 (10/14ma)
(!!!!) (SINGLE) 7581A GE tan base NOS 1965 (62ma)
(!!!!) (Single) E83CC=12AX7 Siemens Halske Germany NOS 1976 (0.7/0.9ma and Gm=1400/1600)
(!!!!) (Single) EF89=6DA6 Telefunken Germany <> bottom NOS 1966 (7.0ma)
(!!!!) 56 Arcturus Blue Balloon engraved base tests like new 1930's (5.0ma)
(!!!!) UX-280 RCA Radiotron Balloon used/60% 1930 era some white oxide flakes inside tube (38/40 and 38/40)
(!!!) (#1 19J6 Pair) 19J6 RCA "U" getter halo NOS 1952 same date codes
