(!!!!) (Best Overall Single) ECC803S=12AX7 Telefunken Ulm Germany <> bottom NOS 1961 1% section balance (Gm=1800/1800) (1.5/1.5ma)
(!!!!) (Recommended Single) ECC803S=12AX7 Telefunken Ulm Germany <> bottom gold pins NOS 1961 (1.3/1.5ma and Gm=1600/1800)
(!!!!!) (2nd Best Pair) ECC803S=12AX7 Telefunken Ulm Germany <> bottom NOS 1961 (1.2/1.3ma and 1.2/1.4ma) 1-2% matched (Nagra, Lamm, VTL, Aesthetix, Diva)
(!!!!!) (Best Pair) ECC803S=12AX7 Telefunken Ulm Germany <> bottom NOS 1961 (1.4/1.45ma and 1.5/1.6ma) 1-2% matched (Nagra, Lamm, VTL, Aesthetix, Diva)
(!!!!) (Best Value Single) ECC803S=12AX7 Telefunken Ulm Germany <> bottom NOS 1961 1-2% section balance (Gm=1550/1600) (1.1/1.1ma)