This is the Famous Mullard 12AU7/ECC82. We mostly have the CV4003 version. The CV stands for "Civilian Valve" which is a military designator for the British military. Any tubes that were designated for the military, by law, could not have the factory logo on them. Often, CV tubes would be re-labeled after decommissioning so it is possible to see a factory logo on a CV tube. These are the real deal Mullard made tubes. Some of the last ones left, these are great sounding tubes with that old European heritage.
The NOS Mullard CV4003/12AU7 is a new never used tube, with low noise and long lasting, in original white military box.
Carefully selected and matched tubes, very low loise and micro. Tubes comes with our certification containing the actually measured information.
A New Old Stock (N.O.S.) tube is an unused tube no longer in production. A N.O.S. tube is good today as it was originally, because the glass sealing techniques perfected long ago have been in use for years and years. A N.O.S. tube can potentially last a lot longer than modern tubes. When we have available a N.O.S. tube stock that comes from the same production run we carefully select them for gain, for section-to-section uniformity and for sensitivity to microphonics. Furthermore, a selected pair of tubes will only include low noise ones.