Matched Pair Sylvania 6C4 Vacuum Tubes Black Plates Copper Support Rods Ken-Rad NOS-Testing I am playing them in

I am playing them in my Mini Mite 2013 and they sound great

Delco-BRANDED 6SK7 tested as good on our Paul Hart-calibrated TV7/U

with a very low noise floor and excellent soundstaging

new in box RCA 14Q7 tubes tested to spec in our Jackson 648 Mutual Conductance tester

Matched Pair Sylvania 6C4 Vacuum Tubes Black Plates Copper Support Rods Ken-Rad NOS-Testing I am playing them inThis almost perfectly matched pair of Sylvania black plate 6C4 triodes was tested on our Paul Hart calibrated TV7 U for shorts, gas and transconductance. There were no shorts or gas. Tube One measured 60 while Tube Two measured 62 where minimum (65%) is 55 and 100% 85. They have top D getters; copper support rods and nice flashing. They sound great in my Alan Eaton single ended 45 amplifier (with an adapter, not included). WE HAVE SCORES OF THOUSANDS