Matched Pair General Electric GE 12SN7 12SN7GT Vacuum Tubes NOS NIB Mini Mite 2013 5 record cleaner and then

5 record cleaner and then played on my Rega Planar Three with an Ortofon X5-MC cartridge

This Raytheon 6JM6A tube is new old stock

Tube One measured 76/76 and Tube Two measured 79/77 where minimum (65%) is 50/50

crenelated rectangular mica spacers

Matched Pair General Electric GE 12SN7 12SN7GT Vacuum Tubes NOS NIB Mini Mite 2013 5 record cleaner and thenThis matched pair of new old stock, new in box (for Tube Two) GE 12SN7GT dual triodes was tested on our Jackson 648 Mutual Conductance tester for shorts, gas, microphonics and transconductance. There were no shorts or gas. Transconductance measured 112% 114% for Tube One and 114% 115% for Tube Two. (New 6SN7s typically test from 2600 micromhos and the Jackson expresses this in terms of a percentage.) These tubes have lyre shaped getters; short bases;