(!!) (Recommended Pair) 12AZ7=12AZ7A GE branded Admiral/Westinghouse black plates NOS 1960 (9.0/9.4ma and 9.2/8.0ma) (McIntosh MC275)

1 pair) 12AZ7=12AZ7A GE branded Admiral/Westinghouse black plates NOS 1960 same build

1 tube) 9.0/9.4ma and Gm=5000/5400 (12AZ7A Admiral)

1 tube) 9.2/8.0ma and Gm=5200/5000 (12AZ7 Wwestinghouse)

Good Ma range 8-10ma

Good Gm range 4500-5500

– 12AZ7A is very similar to 12AT7

– 12AZ7A in McIntosh MC275