(!!!!) (Recommended Pair) ECC82=12AU7 Telefunken Diamond Bottom ribbed plates used/tests like new 1960's (9.2ma/8.4ma and 9.3/9.4ma)
(!!!) (Best Value Single) 12AU7=ECC82 Telefunken smooth plates like new 1963 (10/8.4ma)
(!!!!!) (Nice Single) ECC82=12AU7 Telefunken Germany <> bottom ribbed plates used/good 1957 (8.5/8.2ma) (strong Gm)
(!!!!!) (BEST PAIR) 12AU7=ECC82 Telefunken Germany smooth plates NOS 1961-1965 1-5% matched (10.5/12.0ma and 12.2/10.2ma)
(!!!!!) (Best Single) ECC82=12AU7 Telefunken Diamond Bottom <> smooth plates NOS 1962 (11.0/11.3ma) 1-2% section balance
