(!!!!) (Best Sylvania Pair) 6X5GT Sylvania NOS 1951 (50-53/40 and 52-53/40)
(!!!) (Best Pair 1944) JAN-CHS-6X5GT Sylvania 1944 NOS (53/40 and 54/40 x 2 tubes)
(!!!) (Recommended Pair) 6X5GT GE NOS 1961-1963 (50-50/40 and 49-49/40 x 2 tubes)
(!!!) (Recommended Single) 6SN7GTB Sylvania chrome top gray plates low hours 1950's (8.6ma/8.4ma)
(!!!) (Recommended Single) 6SN7GTB Sylvania NOS 1960's (7.2ma and 6.6ma)
(!!!) (Recommended Single) 6SN7GTB Sylvania used/tests like new 1960's (8.2ma and 7.6ma)
(!!!) (Recommended Single) 6X5GT Sylvania Silvertone NOS 1945 (52/40 and 53/40)
(!!!) (Single) 6X5GT Sylvania Philco NOS 1945 (53/40 and 56/40)
(!!!) 6SN7GTA Sylvania "chrome top" TALL bottle used/good 1950 era (6.2/6.2ma)
(!!) (Best Single) 7N7 Sylvania branded Philco NOS parallel black plates 1940's (7.5/7.9ma)
(!!) 6SN7GTA Sylvania "chrome top" tall bottle used/good 1950 era (6ma/6ma) 1-2% section balance
(!!) 6V6GT Sylvania chrome top NOS 1956 (41.6ma)
(!!) 7N7 Sylvania branded Philco used/good short bottle parallel gray plates 1948 (7.2/7.6ma)
(!!) 7N7 Sylvania NOS 1960's (8.6/10.2ma)
(!) (Best Single) 7N7 Sylvania NOS 1960 era (10.8/11.2ma)
(!) (Good Single) 7N7 Sylvania branded GE NOS 1961-1962 (7.5/8.3ma)
(!) 6AH4GT Hytron by Sylvania "D" getter NOS 1953 (29.3ma)
(!) JAN-CLRV-6SN7WGTA GE Canada brown base NOS 1970 (7/10ma)
(slightly microphonic) JAN-CHS-6SN7W Sylvania "SHORT BOTTLE" used/good 1945 (7.0/7.6ma)
6AH4GT RCA NOS 1960's (17.5ma)