(!!!!!) (Best Overall Pair) ECF80=6BL8 Telefunken Germany <> bottom NOS 1971 (best sound)
(!!!) (Best Mullard Single) ECF80=6BL8 IEC Mullard UK NOS 1966 (16ma/12ma) (Highest mA and Gm)
(!!!) (Best Single) E80CF=7643 Valvo branded Amperex Germany PQ NOS 1961 (Premium 6BL8 SUB) (Highest mA and Gm)
(!!!) (Best Value Pair) 6BL8 Motorola Golden JAPAN by Toshiba "Premium Rated" NOS 1974 (1 pair)
(!!) (Good Value Single) ECF80 VALVO FRANCE (La Radiotechnique) NOS 1962
(!) (Best Single) ECF80=6BL8 Telefunken Germany <> bottom NOS 1961 slightly faded top getter (12.8/25ma) (highest Ma and Gm)
(!) E80CF Valvo Germany rebranded Philips Miniwatt SQ "PINCHED WAIST" NOS 1961 (6BL8 substitute)
(!) E80CF Valvo Germany rebranded Philips Miniwatt SQ "PINCHED WAIST" NOS 1962 (6BL8 substitute)
(!!!!) (Best Single) ECF80=6BL8 Telefunken Germany NOS 1971 (12.8/12.4ma)
7643 Valvo branded Amperex PQ Germany "PINCHED WAIST" NOS 1960 (6BL8 sub)
E80CF Telefunken Germany <> bottom NOS Gold Pins rebranded Siemens 1970-1971 (6BL8 sub)
(!!!) (Best Value Pair) E80CF=7643 Valvo Germany branded International NOS 1961-1963 (PREMIUM 6BL8 SUB) (Tuners) 1-5% matched
(!!!) (Best Value Single) E80CF=7643 Valvo Germany branded International NOS 1961 (12.8/18mA) (PREMIUM 6BL8 SUB) (Tuners)
(!!!) (Best Value Single) E80CF=7643 Valvo Germany branded International NOS 1963 (10.8/13.4mA) (PREMIUM 6BL8 SUB) (Tuners)
E80CF=7643 Valvo Germany branded Philips 1970 (10.5/14.2ma)
E80CF=7643 Philips Miniwatt SQ Germany "PINCHED WAIST" used/good 1961 (11.4/10.4mA) (6BL8 sub)
(!!!!!) (Recommended Pair) E80CF=7643 Valvo branded Philips Miniwatt SQ NOS 1963 (PREMIUM 6BL8 SUB) (Tuners)
(!!!!) (Best Value Pair) ECF80=6BL8 Mullard rebranded GE NOS 1965-1966 (15/16.5ma and 11.2/11.8ma)
(!!!!!) (Best Pair) ECF80=6BL8 Telefunken Germany <> bottom NOS 1971 (best sound)
