Matched Pair Raytheon 6K6 6K6GT Vacuum Tubes Valves Black Plates Clear Bottle 6AL5 Septal I just read the liner

I just read the liner notes and I was right about this album sounding 15-20 years ahead of its time as it was

milspec Sylvania 3Q5GT / JAN-CHS-3Q5GT / VT-221 tubes tested to spec on our Paul Hart-calibrated TV7/U

These mesh plate National Union number 78 tube were tested on our Paul Hart-calibrated TV7/U for shorts

All have JABO codes

Transconductance measured 56 for Tube One and 57 for Tube Two where minimum (65%) is 40

Matched Pair Raytheon 6K6 6K6GT Vacuum Tubes Valves Black Plates Clear Bottle 6AL5 Septal I just read the linerThis matched pair of Raytheon black plate, clear glass 6K6GT tubes was tested on our Maxi Matcher tube tester with 325 volts on the plates and a bias of 36 volts. Tube One drew 21 milliamps' plate current while Tube Two drew 22. 4. Transconductance was 1620 for Tube One and 1730 for Tube Two where new nominal is within one standard deviation of 1900. These tubes have tall bases; black plates; clear bottles and bottom, D getters. As I write, I am