Black Plate
Black BaseNew in White Boxes (NOS)
Made in USA
Amplitrex AT1000 Tested
Offered here is an exceptional vintage matched pair lot of 2 military-grade SYLVANIA JAN 12SN7GT dual-triode audio valves, pristine and clean in crisp white boxes. Made in the USA, these robust, high-performance 12V-heater equivalents to the legendary 6SN7 feature premium Black Plates and a solid Black Base construction, renowned for delivering supreme sonic clarity, rich textures, and classic American audio fidelity.
Each individual tube has been rigorously checked and verified on our laboratory-grade Amplitrex AT1000 digital tube analyzer. Following the exact formatting layout verified in image's. the comprehensive data table below provides the full side-by-side factory parameters alongside the laboratory-measured test results for both triode sections.
| Serial No. |
Test Triode |
Parameter Ip mAdc |
Result Ip mAdc |
% Ip |
Parameter Gm uMhos |
Result Gm uMhos |
% Gm |
| 2347006 |
T1 |
9.0 |
9.4 |
104% |
2600 |
2600 |
100% |
| T2 |
9.0 |
10.6 |
117% |
2600 |
2800 |
107% |
| 2347011 |
T1 |
9.0 |
11.8 |
131% |
2600 |
2800 |
107% |
| T2 |
9.0 |
9.0 |
100% |
2600 |
2600 |
100% |
Note: Custom duties and taxes are the responsibility of the buyer in their country.
Precision Verified — NOS Audio Tubes