Matched Pair General Electric GE 6SN7 6SN7GTB Vacuum Tubes Copper Support Rods NOS-Testing

Matched Pair General Electric GE 6SN7 6SN7GTB Vacuum Tubes Copper Support Rods NOS-TestingThis new old stock TESTING matched pair of GE 6SN7GTB dual triodes was tested on our Paul Hart calibrated TV7 U for shorts, gas and transconductance. There were no shorts or gas. Transconductance measured 82 79 for Tube One and 80 81 for Tube Two where minimum (65%) is 50 50 and 100% is 77 77. They have side, harp getters; copper support rods; great flashing and 56 26 188 4 and 58 13 188 5 date factory codes, respectively. I have played them in my

These nine TCA UY-224 globe

These six new old stock

I have played it in my Musical Paradise 301 MK 3 with an adapter (not included) as a 6SJ7 substitute and it sounds excellent -- airy with excellent dynamics and signal bandwidth

new in box US-made 4BZ6 tubes tested to spec on our Paul Hart-calibrated TV7/U

44 and 46 where minimum is (65%) is 36 and 100% is 55

Both are acid-etched

These four RCA 5847 / 404A gold pin tubes tested to spec on our Paul Hart-calibrated TV7/U

This Sylvania 6SF7 tube tested to spec on our Paul Hart-calibrated TV7/U

new in box RCA 1S4 tubes tested to spec on our Paul Hart-calibrated TV7/U

This is an original recording from 1939 and it sounds 15-20 years ahead of its time

3BL2 and 3BM2

Transconductance measured 2620 micromhos for Tube One and 2650 for Tube Two