(!!!!!) (Best Value Pair) 6SN7GTB RCA NOS and like new 1965 (8.2/10.2ma and 8.2/9.2ma) (same Gm) (warm and smooth)
(!!!!) (Recommended Pair) 12AU7A GE NOS 1958 (9.5/9.3ma and 10.6/9.2ma) (Rogue)
(!!!) (Best Single) 12AU7A RCA clear top NOS 1973 (10.8/11ma) (same Gm)
(!!!) (BEST VALUE PAIR) 12AU7A RCA Bell and Howell and RCA clear top used/good 1960's (8.4/9.0ma and 8.0/8.6ma)
(!!!) (Recommended Single) 12AU7A RCA clear top used/like new "D" getter halo 1960's (9.0/10.8ma)
(!!) (BEST VALUE SINGLE) 12AU7A RCA clear top used/good 1960's (8.0/9.4ma)
(!!) (Recommended Single) 12AU7A RCA top getter NOS 1970 era (10.2/11ma)
(!!) 12AU7A CBS black plates NOS 1960 era (9.5/11.8ma)
(!!) 12AU7A RCA clear top used/good 1960's (7.4/8.6ma)
(!!) 12AU7A RCA clear top used/good 1964 (8.2/8.6ma)