Matched Pair Sylvania 6AU6 Vacuum Tubes Valves NOS-Testing RCA Black Plate I have played it in

I have played it in one of my ArtSound 805 monoblocks and it sounds excellent

a fence-like strip on top of the top spacer and dimpled sheet getters

Transconductance readings are indicated on the tops of the tubes

black plate 12AT7WA / ECC81 dual triode was tested on my Hickok 600A for shorts

Matched Pair Sylvania 6AU6 Vacuum Tubes Valves NOS-Testing RCA Black Plate I have played it inThis new old stock testing matched pair of Sylvania 6AU6 tubes was tested on our Paul Hart calibrated TV7 U for shorts, gas and transconductance. There were no shorts or gas. Transconductance measured 82 for Tube One and 84 for Tube Two where minimum (65%) is 58. These tubes have top, U getters; gray plates and excellent flashing. I am playing them in my Musical Paradise MC 3 single ended integrated amplifier (with adapters, not included) with Aimee