Sylvania 12AU7 ECC83 Early Production Black Plate Copper Support Rods Vacuum Tube For Your Bottlehead Berman Plays Liszt This new old stock-testing RCA

This new old stock-testing RCA 12BH7A was tested on our Maxi Preamp II for shorts

It measured 80 where minimum (65%) is 50 and 100% is 77

top chamfered solid-O getters and two additional vertical support rods for increased rigidity and lowered microphonics

5 record cleaner and then played it on my He-Man Rig which consists of a Rega Planar Three with an Ortofon X5-MC cartridge on an RB-300 tone arm with a Cern Audio Dual 6SN7 / 6SL7 phono preamp / preamp feeding my Bottlehead headphone amplifer driving Sennheiser HD 580 cans

This lot of eight new old stock

Sylvania 12AU7 ECC83 Early Production Black Plate Copper Support Rods Vacuum Tube For Your Bottlehead Berman Plays Liszt This new old stock-testing RCAThis Sylvania 12AU7 ECC82 dual triode was tested on our Paul Hart calibrated TV7 U for shorts, gas and transconductance. There were no shorts or gas. Transconductance measured a nicely balanced 68 72 where minimum (65%) is 56 56 and 100% is 86 86. This tube has black, slightly shiny ladder plates; excellent flashing; a top, slanted D getter; copper support rods. This is an early production 12AU7. It is not a 12AU7A WE HAVE SCORES OF THOUSANDS OF