National Union NU 6F6 6F6G Vacuum Tube ST Shoulder Shape NOS-Testing

National Union NU 6F6 6F6G Vacuum Tube ST Shoulder Shape NOS-TestingThis NOS testing National Union 6F6G output tube was tested on our Paul Hart calibrated TV7 U for shorts, gas and transconductance. There were no shorts or gas. It measured 76 where minimum (65%) is 50 and 100% is 77. WE HAVE SCORES OF THOUSANDS OF VACUUM TUBES. IF IT'S NOT LISTED, WE MAY HAVE IT. PLEASE ALSO SEE OUT ETSY SISTER SITE "LOWTECHTWOO" AND OR CALL OR TEXT US AT 202 372 6931 IF YOU DO NOT SEE WHAT YOU NEED OR HAVE ANY QUESTIONS. 1. MOST

I am playing them in my ArtSound single-ended 805 monoblocks with Steely Dan’s seminal "Aja" album

new in box RCA 53HK7 tubes

There is no mounting hardware or coax

IT IS YOUR RESPONSIBIILTY TO INTERACT WITH YOUR CUSTOMS AND POSTAL AUTHORITIES TO FIND THE PACKAGE

It is dead quiet when the preamp is muted and has excellent frequency response and dynamics even though it tests poorly

The 7025 has somewhat-different gain characteristics than the standard 12AX7

These tubes have copious flashing

It measured 44/40 where minimum (65%) is 50/50 and 100% is 77/77

5 volts with adapters (not included) and they sound tremendous even though they straddle the cusp and are running with a lowered filament voltage

new in box GE 6GF7A tubes tested to spec on our Paul Hart-calibrated TV7/U

This Sylvania 5933 / 807W / FU7 output tube was tested on our Maxi-Matcher 2 for shorts

This new old stock-testing matched pair of GE 12SN7GT dual triodes was tested on our Paul Hart-calibrated TV7/U for shorts