Sylvania 7F7 Vacuum Tube March 21 2023 THIS IS NOT AMAZON

THIS IS NOT AMAZON

For sale is one new old stock

Tube One measured 40/44 while Tube Two measured 42/46 where minimum (65%) is 25/25 and 100% is 38

Converter 12BE6

This tube has steel support rods

Sylvania 7F7 Vacuum Tube March 21 2023 THIS IS NOT AMAZONThis Sylvania 7F7 was tested on our Paul Hart calibrated TV7 U for shorts, gas and transconductance. There were no shorts or gas. It measured 42 44 where minimum (65%) is 33 33 and 100% is 51 51. I have played it in my Cern Audio phono pre preamplifier as a 6SL7 substitute (with an adapter, not included) and it sounds outstanding. It is dead quiet when the preamp is muted and has excellent frequency response, sound staging, and dynamics It is somewhat