(!!!!) (Best Pair 1966) 12AU7A GE NOS 1966 (9.8/10.6ma and 11.2/9.8ma) (Close Gm) (Warm and smooth)
(!!!!) (Best Pair) 6AC7 RCA NOS 1960's (11ma and 11.8ma)
(!!!!) (Best Pair) 6AC7 RCA NOS 1961-1962 (10.3ma and 10.6ma)
(!!!!) (BEST SINGLE) 12AU7A GE NOS 1963 copper grid posts (11.4/11.6ma) 1-2% section balance
(!!!!) (Recommended PAIR) 6AC7 RCA NOS 1961 (11.4/12.4ma)
(!!!) (BEST PRICE) 12AU7A GE used/good 1969 - 1980 (4 for $29.99)
(!!!) (BEST PRICE) 12AU7A GE used/good 1971 - 1978 (4 for $29.99)
(!!!) (Recommended Pair) 12AU7A GE NOS 1965-1975 (8.8/8.8ma and 9.2/8.8ma) (Same Gm) (smooth and warm)
(!!!) (Recommended Pair) 6AC7 RCA NOS 1950's (11.5ma and 12.2ma)
(!!!) (Recommended Pair) 6AC7 RCA NOS 1970 era (10.0ma and 10.5ma)
(!!!) (Recommended Single) 12AU7A GE NOS 1963 (8.6/9.5ma)
(!!!) 12AU7A GE "U" getter like new 1959 (10.8/10.2ma)
(!!!) 12AU7A GE "U" getter low hours/tests like new 1957 (10.0/8.8ma)
(!!) (Best GE Pair) 6AC7 NOS 1960's - 1970's (13ma/13.5ma)
(!!) (BEST PRICE) 6AC7 Mixed US Brands (4 tubes for $14.99)
(!!) (BEST PRICE) 6AC7W RCA used/good (4 tubes for $8.99)
(!) (GOOD VALUE PAIR) JAN-CRC-6AC7=VT-112 US Brands 1941-1944 used/good (7.0/7.1ma)
(!) (Recommended Pair) USN-CRC-6AC7 RCA mid-1940's used/test like new (10.6/11.0ma)
(!) 6189=12AU7A GE NOS 1975 (9.6/10ma) 1-2% section balance
6AC7 Ken Rad NOS 1940's (14ma)