The NOS Mullard M8137 / 12AX7WA / ECC83 is a new never used tube, with low noise and long lasting, in original Mullard box. Exact equivalent to the European ECC83 code tube and can be used in any 12AX7 circuit/application.

Mullard M8137 (CV4004) can be considered the 'King' of all ECC83.
Please take a look at this stunning valve. This is for sure the best valve ECC83 money can buy! We have several pairs in stock and boxed. Highly unlikely that we will see these again. Complete and harmonically rich tone. The sound stage is detailed and relaxed and it handles complex music with ease. Superb mid band. Unbelievable bass and punch. The M8137 is famous for low microphony and dynamics. Balanced triodes. If you are looking for the absolute this is the one for you.

Carefully selected and matched tubes, very low loise and micro. Tubes comes with our certification containing the actually measured information.

- Old logo
- Large round getter ring
- Boxed anode
- Mullard boxed
- NOS and NIB

Limited stock.

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.

Information on tube matching