Sylvania 12AV7 Vacuum Tube Valve Black Plate NOS-Testing 17BZ3 T18 a round mica spacers and

a round mica spacers and gray plates

respectively

new in box matched pair of JJ low noise 12AX7 / ECC83 / 12AU7 dual triodes was tested on our Paul Hart-calibrated TV7/U for shorts

The number will change as time goes by and Etsy will indicate how many are still available

Sylvania 12AV7 Vacuum Tube Valve Black Plate NOS-Testing 17BZ3 T18 a round mica spacers andThis new old stock testing Sylvania 12AV7 dual triode was tested on our Jackson for shorts, gas and transconductance. There were no shorts or gas. Transconductance measured 116% 104% where minimum (65%) is 70% 70%. This tube has black plates; a horseshoe getter and terrific flashing. I am playing it in Bottlehead Crack headphone amplifier as a 12AU7 substitute and it sounds excellent. WE HAVE SCORES OF THOUSANDS OF VACUUM TUBES. IF IT'S NOT LISTED, WE