Matched Pair General Electric GE 6SJ7 6J8P Vacuum Tubes NOS-Testing 9002 Septal new in box US-made 6F7

new in box US-made 6F7 tubes tested to spec on our Paul Hart-calibrated TV7/U

It measured 42/49 where minimum (65%) is 50/50 and 100% is 77/77

It is dead quiet when the preamp is muted and has excellent frequency response

dynamics and frequency response

This album was recorded and manufactured in the Soviet Union

Matched Pair General Electric GE 6SJ7 6J8P Vacuum Tubes NOS-Testing 9002 Septal new in box US-made 6F7This new old stock testing, perfectly matched pair of GE 6SJ7s was tested on our Paul Hart calibrated TV7 U for shorts, gas and transconductance. There were no shorts or gas. Transconductance measured 77 for both tubes where minimum (65%) is 40. They have 56 26 188 4 and 61 26 188 4 date provenance codes, respectively. I am playing them as I write in my Musical Paradise MP 301 MK3 and they sound excellent. WE HAVE SCORES OF THOUSANDS OF VACUUM TUBES.