I often find this lamp in pedals or amp type Valvestate and all lamps and now it's a REFERENCE: hot lamp with a lot of momentum. It has a good amount of gain and suffers from some of microphonie.Pas dsequilibre in the sound spectrum and a grain inimitable ...
Finally it may be that makes me a note at decendre final board as it is home to a bunch of stuff, the sound does not flatter myself the ear as the ground tung 12 AX 7 or DD ECC 83.
A standard