Matched Pair Sylvania Black Plate 12BY7 12BY7A Vacuum Tubes Valves T16 Transconductance measured 116%/104% where minimum

Transconductance measured 116%/104% where minimum (65%) is 70%/70%

I am playing them in my Musical Paradise MP-301 MK3 as I write and they sound excellent

new in box International Servicemaster 6CG8A tube tested to spec on our Paul Hart-calibrated TV7/U

new in box GE 6HB7 tubes tested to spec on our Paul Hart-calibrated TV7/U

Matched Pair Sylvania Black Plate 12BY7 12BY7A Vacuum Tubes Valves T16 Transconductance measured 116%/104% where minimumThis matched pair of Sylvania black plate 12BY7 12BY7A tubes was tested on our Paul Hart calibrated TV7 U for shorts, gas and transconductance. There were no shorts or gas. Tube One measured 54 while Tube Two also measured 54. (Minimum (65%) is 46 and 100% is 71. These tubes have black plates; chamfered O getters and rectangular radiators for cooler operation and longer tube life. WE HAVE SCORES OF THOUSANDS OF VACUUM TUBES. IF IT'S NOT LISTED, WE MAY