(!!!!) (Best Single) EZ81=6CA4 Philips Australia NOS 1974 (58/40 and 58/40) (similar sound to EZ81 Holland) 1% section balance
(!!) (Recommended Pair) 6GK5=6FQ5A GE NOS 1968-1981 (10.4ma and 11.2ma)
(!) (BEST OVERALL PAIR) 6AV6 Super Radiotron Australia NOS 1960's (1.6ma and 1.7ma) (same Gm)
6DQ6A Super Radiotron Australia NOS (69ma)
6DQ6B GE branded Amperex NOS/77% 1970 (58ma)
6DQ6B JAPAN NOS 1960's (64.5ma)
